This last template is made in Microsoft Excel, and includes space for a larger number of rows (download the template).
Always start by defining the start and end points in the process
column – these boundaries are important as the team defines the
processes that are included between these start and end points.
Next, document the process steps themselves. There are no firm
guidelines for doing this, but four to seven process steps seem to work
well in most situations. If the team is coming up with too many process
steps, they should consider creating more high-level process steps and
then creating lower level SIPOCs to define each of the high-level
After completing the process steps, proceed from the center of the
document to the right, adding process Outputs and then Customers.
Then work from center to left, adding the Inputs and Suppliers of those
Creating a SIPOC diagram is best done in a team setting, following a
specific sequence of steps: (1) Processes, (2) Outputs, (3) Customers,
(4) Inputs, (5) Suppliers.
This center-out approach works very well since most teams can quickly
recite their work processes, but do not always know who their customers
and suppliers are. This is especially true in large companies where
functions are often siloed, with little supplier and customer
Creating a SIPOC Diagram in 5 Steps
Define the beginning and ending processes for the SIPOC, and place them at the top and bottom of the Processes column,
as noted above. Then note the processes that go in between the
beginning and ending processes. This completes the Processes column.
Identify the Outputs that the Processes from step (1) deliver. List them in the Outputs column.
Identify the internal and external Customers that receive the Outputs from Step (2), and list them in the Customers column.
Identify the Inputs that the Processes from step (1) require in order to perform their function, and list them in the Inputs column.
Identify the Suppliers that provide those Inputs, and note them in the Suppliers column.
Building a SIPOC diagram in a team setting
SIPOC diagrams can be made quickly in a team setting, typically in an
hour or less. Here are a few suggestions for planning and running the
Select a Small Team – Since SIPOC’s are high-level
documents, they can usually be made with a small team of supervisors or
managers who understand the overall process at a high level.
Show an Example – At the beginning of the meeting, show a completed SIPOC example to help convey the desired outcome of the meeting.
Sticky Notes – Use large sticky-notes and make the SIPOC on a
blank wall or whiteboard. This allows for quick repositioning of the
SIPOC elements without erasing and re-writing them. Another option is
to use one of the templates on a computer with a projector screen.
Follow the Above Sequence – Following the above
center-out sequence works well in team setting, and the process goes
quickly once the center (Processes) column is filled in. To complete
the additional columns, simply ask,
“What are the outputs of these processes?”
“Who are the customers that receive these outputs?”
“What inputs are required by these processes?”
“Who are the suppliers that provide these inputs?”
Working through obstacles
Here are a couple of obstacles that can come up during a SIPOC diagramming session, and suggestions for working through them –
Too Much Detail – this is a common problem, where some team members may push for too much detail in the SIPOC. A cluttered diagram will result if this situation is not managed. Generally speaking, more than ten items in any column is too many. Here are some options for avoiding too much clutter in the diagram –
Group similar items together. Remember that a SIPOC is a high-level document, not a detailed process flow chart. See in the manufacturing example where equipment builders were simply noted as “Equipment Builders,” in the Suppliers column rather than being listed out individually.
Add supplemental documents, separate from the SIPOC. Continuing with the equipment builder example directly above, a page-2 reference document could be added to the SIPOC, listing the equipment builders.
Narrow the scope – if the team cannot consolidate similar items together, then consider changing the scope and using two SIPOC diagrams. For example, break up a customer service team’s SIPOC into two documents: (1) Order Entry and Logistics Support and (2) Post-Delivery Support.
• Introduction 1. A brief history of Quality 2. What is Quality (Definitions) and service or product 3. Quality Gurus & their contribution to Quality 4. Enterprisewide View 5. Leadership 6. Six Sigma Roles and Responsibilities 7. Team Formation 8. Team Facilitation 9. Team Dynamics 10. Time Management For Teams 11. Team Decision making Tools 12. Management and Planning Tools 13. Team Performance Evaluation And Rewards 14. Overview of DMAIC
• Define 1. Important Stakeholders 2. Impact On Stakeholders 3. Critical To X Requirements 4. Benchmarking 5. Business performance measures 6. Financial measures 7. VOC 8. Kano’s Customer Satisfaction Levels 9. Juran’s customer needs 10. Market research 11. CTQ Flowdown 12. QFD 13. Performance Metrics 14. Project Charter 15. Charter Negotiation 16. Project management plan and Baselines 17. Project Tracking
• Measure 1. Processes, Process characteristics, process flow metrics, inputs and outputs 2. Process maps and Flow chart 3. SIPOC 4. Data Type & Measurement scale 5. Data Collection 6. Sampling strategies 7. Fishbone Diagram 8. Relational Matrices or Prioritization Matrix 9. Basic Statistics 10. Analytical Statistics 11. Gauge R & R 12. Process Capability Analysis
• Analyze 1. Correlation and Regression Analysis 2. Testing of Hypothesis 3. FMEA 4. Gap Analysis 5. The Five Whys 6. Pareto Diagram 7. Tree Diagram 8. Non-value added activities 9. Cost of Poor Quality (COPQ)
• Improve 1. DOE 2. Poka-yoke 3. 5S 4. SMED 5. Continuous Flow Manufacturing 6. Kaizen 7. Kanban 8. Theory of constraints 9. Risk analysis
• Control 1. Statistical Process Control 2. Other Control Tools 3. Maintain Controls 4. Sustaining Improvements
• DFSS 1. DFSS
• Case Study 1 1. Case Study 1 Part 1 2. Case Study 1 Part 2
• Case Study 2 1. Case Study 2 Part 1 2. Case Study 2 Part 2
Курсът съдържа цялата
информация, необходима за успешно полагане на изпита. Учете от всеки
компютър и от всяко място, когато и колкото искате! Не са необходими
никакви специални технически средства. Можете да повтаряте материала и
тестовите въпроси неограничен брой пъти.
В цената са включени официален сертификационен изпит Six Sigma Black Belt (180 минути, 125 въпроса) и сертификат при успешен изпит. Изпитът се провежда онлайн на предварително заявени от Вас дата и час.
Предварително условие: Six Sigma Green Belt
Насладете се на богато учебно съдържание и модерни и ефективни учебни инструменти! Курсът Six Sigma Green Belt включва:
A process map is an important part of any Lean Six Sigma project –
it helps communicate the process at the center of your project and
guides you to specific areas of focus. There are a number of choices
available, and choosing the right map helps to clarify your efforts.
The wrong map might confuse matters or simply waste your time. I’ll share key aspects of the following map types:
The intent is to help you make a useful choice, but not go into how
to build each map. If you Google each map name you’ll find examples and
guides for constructing them and there are links to helpful templates
for some of them. Keep in mind that there are plenty of opinions on the
“right” way to make them – find what works for you.
Map #1: SIPOC
SIPOC is an acronym for Supplier – Inputs – Process –
Outputs – Customer, and may not be considered a true process map by a
purist. I like to think of it as a “one box” process map. That might not
seem like much of a map, but it establishes the basis for subsequent
The importance of the SIPOC
is that it shows, in very simple terms, what the process accomplishes
while identifying the key players. The center contains the a few
high-level process steps. The required inputs (and their providers) are
listed to the left, and the key process outputs (and their recipients)
are listed to the right. The SIPOC provides a focus for discussion of
what the process is all about.
The importance of the SIPOC is that it shows, in very
simple terms, what the process accomplishes while identifying the key
In this case we are examining the purchasing process in which a
requester submits a purchase requisition that details what’s to be
purchased. The requisition is received and a purchase order is issued to
a supplier, who subsequently delivers what was ordered. The SIPOC also
can define the scope of
the project: in this case, the process of converting a request into an
order placed with the supplier. It does not include the actual delivery,
the invoicing or the payment. The SIPOC would have different outputs or
customers if the project had a broader scope.
I recommend creating a SIPOC for every project because they are
helpful when discussing the process with others and they’re incredibly
simple to make! Your first SIPOC may feel a bit awkward, but with a
little practice you can make a SIPOC for nearly any process in less than
The SIPOC discussed here is the simplest form – there have been many
improvements, including the SIPOC-R (discussed next), and the
GoLeanSixSigma version, which actually combines the SIPOC with a high
level process map (see https://goleansixsigma.com/sipoc/).
The SIPOC-R is a variation on the SIPOC in which the
requirements (or specifications) for the inputs and outputs are listed,
typically just under each input or output. In this case, a proper
requisition might include the item description, date needed, an account
number to charge, and an authorizing signature. Often the additional
detail provided by requirements offers clues to problems we might wish
to solve. If the problem exists even though all of the input
requirements have been satisfied, then the cause is either in the
process itself or in a missing (unstated) requirement. On the other
hand, if the requirement has not been met, we should investigate the
causes and you may not need to delve into the process details.
If we need to examine the process, we want to make sure we see how
the process converts the SIPOC inputs into the outputs, so the SIPOC can
help us avoid missing some important relationships.
Map #2: High Level Process Map
High Level Process Maps show how the process works
in just a few steps. The purpose is to provide quick and easy insights
into what the process does, without getting into the details of how it’s
done. This can be useful when communicating to leadership and others
who have no need (or interest) in seeing the details.
High Level Maps typically don’t require a deep knowledge of the
process, so you can often construct them with the assistance of
managers. Think of the High Level Map as simply an expansion of the
center “process” from the SIPOC into five to ten more detailed boxes.
This map shows where all the inputs go, and where all the outputs are
High Level Maps typically don’t require a deep knowledge
of the process, so you can often construct them with the assistance of
In this case, each function or department is shown in a different
color. This isn’t essential, but it’s useful. In most projects a High
Level Process Map is adequate to describe the process. As you
investigate underlying problems, you can put marks next to the steps
(dot’s, x’s, stars) when you find problems originating in that step.
When complete, it forms a visual concentration diagram, showing where
the problems lie in the process.
Map #3: Detailed Process Map
We don’t normally need to see the entire process in detail, but there may be some parts of the process that require a Detailed Process Map.
This is especially true if there are a number of problems with that
step. In this example, we might be interested in exploring the
Purchasing step. We simply consider the input to that step, identify
what immediately happens with that input and then repeatedly ask the
“what happens next?” question until we produce the output. If this
provides the necessary level of detail, we can stop here. If, however,
we need to know more about the “Get three quotes” part of the process,
we could explode it into more detail. The key is selectively
diving into the detail. It’s a lot of work to create a detailed process
map – you need to talk to the people who work the process in order to
find out what really happens – managers often don’t know the process at
this level of detail. I prefer to start with a High Level Map and let
the needs of the project dictate when to go into more detail and how far
to dive down.
The exception is if we intend to radically streamline the process. In
that case we have to get close to the “work instruction” level of
detail in order to isolate the few nuggets of the process that are truly
The exception is if we intend to radically streamline the process.
Finding value-added activities
in a process cannot be done in a High Level Process Map. In fact, if
the value-added activity is evenly distributed throughout the process,
then at a high level, all of the steps will appear to be value-added
because they all contain an activity that contributes value. If you blow
up each step into its detail you will find that the true value-added
activity is isolated in one or two small steps.
Map #4: Swimlane Map
Swimlane Maps separate the steps into lanes or
channels according to who does the activity. If we have a process map
where the participants have been identified by departmental colors,
simply “sliding” the steps so those of the same color line up in a
horizontal row, it becomes a Swimlane Map.
This Swimlane Map is especially helpful when establishing
work instructions and training for the new process because it makes
each participant’s role explicit.
This style of process map is highly valued because it clearly shows
“who does what,” when they do it and an arrow crossing a lane indicates,
a handoff. For this reason, Swimlane Maps are favored by managers who
who appreciate additional information. The drawback is that Swimlane
Maps are not space efficient, especially if there are multiple lanes
with few steps. In such maps some lanes are nearly empty which means
the overall process map takes up more space. In addition, processes with
a lot of handoffs can be awkward to depict in a Swimlane Map since they
result in many arrows crossing multiple lanes. My preference is to use
traditional, high level and detailed maps during the project work, and
use the Swimlane Maps for the improved process since it will be simpler
with fewer boxes, participants and handoffs. This Swimlane Map is
especially helpful when establishing work instructions and training for
the new process because it makes each participant’s role explicit.
Map #5: Relationship Map
Relationship Maps are technically not process maps
since they don’t detail the work done, but they do show the participants
and how materials, paper or information flows between them. This map
was popularized by Rummler-Brache, and is not widely used, but I wanted
to share it as an option. This map is useful when initially exploring
the process, typically at a high level, to determine the identity of
If there are only a couple of
participants in the process there is no point in creating a Relationship
Map, but if there are many participants it is a helpful addition to a
High Level Process Map. Once you have created a Relationship Map, you
can use it to complete your process map by confirming that the arrows in
the Relationship Map originate from the steps creating the unit and end
in the proper place.
Map #6: Value Stream Map
Value Stream Maps are typically used in Lean
applications where we are interested in either showing pull scheduling
or opportunities to do pull scheduling. They are often detailed and
difficult to read. However, they are rich with information that is
useful when planning process improvements. Value Stream Maps
are often used when planning a Lean implementation to display the
current state of the process including material flows, information flows
and other information important for Lean implementations.
A few distinguishing features:
Material moves from left to right
Information which triggers release of materials or scheduling of production moves from right to left
Work-in-Process (WIP) is shown in the triangles
Relevant process details such as cycle time, changeover time, etc. are shown below each process step
Wait time and work time appear on a line at the bottom of the map
Improvement opportunities appear as starbursts
They require more skill to build than simpler process maps, but they provide great information.
Value Stream Maps are sometimes called Material and Information Flow Diagrams.
They require more skill to build than simpler process maps, but they
provide great information. For this process, the diagram shows there is
essentially neither pull nor flow, a little over a day’s worth of
work-in-process inventory and lots of wait time. The process should
produce one part every 18 minutes (takt time)
to meet the customer demand, but four of the five process steps cannot
meet this output pace. It takes 6.56 days for a part to get through the
process (though it’s needed in 5 days), after receiving 108 minutes of
work. An experienced Lean practitioner will quickly see a lot of
Choosing the Right Map
It may seem that I am advocating the Value Stream Map, but I am not.
For Lean implementations it is helpful, but for routine problem solving
it may be substantial overkill. So how do we choose the right map for
the job? The following chart provides guidance:
Many projects make use of several maps types. You might start out
with a SIPOC, followed by a High Level Map. After some investigation you
might decide to make a detailed map of selective portions of the areas
where problems exist. After finding root causes and creating a revised
process, the Swimlane Map can provide helpful documentation.
stream mapping (VSM) is a lean manufacturing tool that seeks to map
your process from supplier to customer, highlighting the flows of
product and information and identifying delays and non-value adding
It is a top level view of your company rather than a
detailed look at an individual process within it, but this map is a real
eye opener for top management. This is one of the most powerful and yet
easy to use mapping tools at your disposal and can lead to a rapid and
significant improvement to your business if action is taken following
the mapping exercise.
VSM is not just about creating one map; it
is about discovering where we are today with a current value stream map
and using the team to create an ideal state value stream map as a target
to aim for whilst creating a series of future state maps to work
towards on the journey to our ideal state.
Why do we need VSM
Value Stream Map
need value stream mapping to create a common vision and direction for
our company, a current state map created by those involved in the
processes creates buy in and understanding as to where we are. The
creation of an ideal state together provides that shared vision that all
can buy into and work towards.
The creation of future state maps
and related action plans help to generate improvements and change within
the company worked on by all.
Lean we are trying to compress the time from order receipt through to
the cash arriving in our bank account, This best done through an
evaluation of the value stream as a whole, not just concentrating on the
small period of our lead time taken up by manufacture.
What do we Map?
stream mapping is usually conducted on a single product or family of
products from supplier through to customer. Where we have multiple
products it is tempting to try to map them all but this would just
result in information overload.
The team should choose one product
or family on which to create the map, any improvements made on this
value stream can then be used as a template to improve other value
streams. At times it is difficult to find product families if you have a
large number of individual products. Product family analysis is a
useful tool to use to find the similarities between products to allow
the creation of families.
How do we VSM
stream mapping is a team process that should take place at the gemba
(the workplace), not within an office by an expert using data from
written procedures about what should happen. Your value stream map
should reflect exactly what does happen along with real current data
regarding stock levels, delays, change over times, quality levels and so
forth. It is this map that will form the basis for your improvements.
Ideal and Future state Value stream maps
you have your agreed version of your current state map it is time to
move directly onto creating your ideal and future state maps.
ideal state value stream map requires a firm understanding of lean
manufacturing principles to enable the team to visualize an ideal lean
process. This would often be a single dedicated cell controlled through a
pull kanban system rather than a grouping of shared processes each
scheduled from an MRP system pushing product onto the next process, with
daily or even hourly deliveries to customer and from supplier. The
ultimate ideal of course being single piece flow at the demand of the
Often it is impossible to jump straight from the
current state to the ideal so the team needs to agree a future state map
to work towards on the journey to the ideal state. This then becomes
the basis for an action plan; you may wish to first work at
standardizing and improving processes to improve cycle times and reduce
defects or whatever the most pressing issue is for your business
highlighted on your VSM.
is a step by step guide to creating a current state value stream map,
the first step in working towards your ideal state value stream and a
truly lean system. Your current state value stream map is a team effort
that is conducted by those people who are involved in the process, at
the actual process, not by an expert locked in a room with a pile of
Below we will go through;
Selecting the product (family) to map
Defining the process boundaries
The Process Steps
Calculating the Time Line
Multiple Suppliers and Customers
Interpreting the Data
Next Steps (Ideal and future state maps)
You can also download a free Value Stream Mapping presentation in PPT and PDF format that goes with this page:
Value stream map is a representation of the flow of materials from
supplier to customer through your organization as well as the flow of
information. This enables you to see at a glance where the delays are in
your process, any restraints and excessive inventory. Your current
state map is the first step in working towards your ideal state for your
How to create a VSM
stream mapping (VSM) is a team exercise and should involve
representatives from all of the areas within the process being mapped,
this process should be facilitated and led by an expert with experience
in creating value stream maps. A value stream map is best created by
hand using a pencil (you will need to make frequent corrections and
changes) on a sheet of A3 paper. It is better to create by hand and
involve the entire team in its creation rather than have an expert take
the information and return later with a finished map!
Step by step guide to Value Stream Mapping;
Select the product or product family
Use a simple matrix to show products that use the same process route.
we need to decide what it is exactly that we wish to map, in a company
with many products there may have to be some initial work done to
identify which product or family group of products that should be
mapped, we may decide to go with highest volume or value, or take a
longer term strategic look at those product ranges that we expect to do
more business with in the future or we may be guided by our customers as
to what to map.
If we have a plethora of products we may wish to
first conduct a product family analysis, this is a simple review of our
products and which processes they go through. It may not be necessary
to analyze all products, use a Pareto analysis to decide which products
you need to analyze (either through volume or value or a combination.)
This analysis can help us group together products that share common
routing through our processes. Our value stream map can then concentrate
on either a single product or a family of them sharing common
Value Stream Mapping Symbols
Some of the symbols for use in VSM
picture to the Left shows some of the commonly used value stream
mapping symbols and their meanings. It is not necessary to use these
specific symbols, if you have symbols that are more relevant /
descriptive for your processes then use those.
Bound the Process
need to decide the limits of our map, most value stream maps are
conducted from supplier through to customer within an organization and
these should be the first boxes placed on your VSM to bound the process.
It is possible to map the entire supply chain, in this case the start
and end points for your process map would be the raw materials and the
final consumer, instead of putting boxes for process steps thereafter
however you would use companies.
Add process boundaries and process steps to your VSM
you have your process boundaries established you need to define your
process steps for your map, some people advocate walking the process
from customer back to supplier or the other way around, quite frankly it
does not matter too much which way you do it.
process steps are the various operations that are performed on the
product, these are generally located in a single place with one point
that inventory enters and then leaves. We are not breaking down each
operation into specific tasks, there are other process mapping techniques such as flow charting that would be a better tool for analyzing to that level of detail.
Add Information Flows to your Value Stream Map
Add information flows to your VSM
of the things that differentiates a VSM from most other mapping tools
is the inclusion of the information flows into the map. We need to
include how the customers order product, frequency and method, and how
we translate that back to our supplier. We also include how we then
communicate requirements to our processes to ensure that we produce what
the customer wants.
Collect Process Data
where we need to do a little thinking and some work, get the team to
collect data regarding the performance of each step of the process;
typical types of date to collect are;
Cycle time (time taken to make one product)
Change over time (from last good piece to next)
Up-time (on-demand machine utilization)
Number of operators
Net available working time
Pack size/pallet sizes
Add data to data boxes on your Value Stream Map
the relevant measures for your process and record actual data at the
workplace, try to avoid “historical” measures where possible, get your
own current information. If you do use timings and other data from the
“system” to save time make a note of those measures and ensure that you
go back and verify them during the action phase. Record this data in the
“data boxes” on your Value Stream Map
Inventory and overproduction are two of the biggest of the seven wastes of lean
and tend to occur when we have problems in our production processes. We
use excess inventory to cushion ourselves against process problems so
careful note should be taken of inventory build up. When counting
inventory for your map question carefully as it is not unusual to find
pallets of inventory stored in odd locations due to previous problems or
as a contingency.
Our completed current State Value Stream Map
create the time line to give us information about total process times
and lead times for inventory through our processes; we use the inventory
at each stage and the daily demand to calculate the amount of stock in
days and add this to the top of the time line, this will allow us to
calculate a total lead time. The cycle time for one product is then
placed in the lower portion and this will be added to give a total
It is usual to at this point to have lead times
that are several days to several weeks and processing times that are are
only a few minutes which highlights just how much waste there is in our
This gives us our completed current state value stream map; now the real work can start.
Multiple Suppliers and Customers in VSM
map produced above is a fairly simple map with just one customer and
one supplier, more often than not we have multiple suppliers and
customers and it may be necessary to draw on more than one. In this case
the process is still the same but when you calculate your timeline use
the worst case for inventory. If you have many suppliers it may be worth
concentrating on your most important suppliers or grouping them into
similar types such as fasteners.
More often than not you can still
show multiple customers as one, or if required as groups with similar
requirements such as weekly or monthly demands.
Interpreting the Value Stream Map
data boxes and the timeline contain much information about our process,
you can now see in one document where the problem areas within your
process lie, issues such as;
Long cycle times
Excessive Setup Times
Poor Quality / Rework
Creating an Ideal and Future State Value Stream Map
problems highlighted above could all be tackled one by one; but what we
really need is a vision of where we want to end up so that we can focus
our efforts on achieving an agreed “Ideal State.” The team guided by
the expert should create an ideal state value stream map which should
envision the absolute best the process could be, this should then be
agreed by senior management as the ultimate goal of your value stream
mapping exercise. This Ideal state could be a single cell rather than
isolated process silos in different parts of the factory with daily (or
more frequent) deliveries to the customer and from the supplier. Kanban
systems could be utilized to remove the need for planning and scheduling
as well as many other ideas that could be considered.
Moving from Current state through an iteration of future state maps towards our Ideal
you have your ideal state then you can plan to achieve your shared
vision of where the process needs to be; the simplest way to do this is
to plan a series of improvements, each taking two to three months, and
use your value stream map to communicate what you want to do. Use the
kaizen burst symbol on your current state map to highlight the
improvements that you want to make, for instance reducing the setup time
on the final test from 20 minutes to 5 minutes, your aspirations for
your improvements become your future state value stream map. You may
need several iterations of future state maps before you finally reach
your ideal state.
A bell curve (also known as normal distribution curve) is a way to plot and analyze data that looks like a bell curve.
In the bell curve, the highest point is the one that has the highest
probability of occurring, and the probability of occurrences goes down
on either side of the curve.
It is often used during employee performance appraisals or during evaluation in exams (ever heard – “You will be graded on the curve?”).
Now before I jump in on how to create a bell curve in Excel, let’s
get a better understanding of the concept by taking an example.
Understanding the Bell Curve
Suppose you work in a team of 100 members and your manager tells you
that your performance will be relative to others and will be evaluated
on the bell curve.
This means that even if your team is the best team ever and you’re
all superheroes, only a handful of you would get the top rating, most of
the people in your team would get an average rating, and a handful will
get the lowest rating.
Suppose you have a class of 100 students that appear for an exam.
According to your grading system, anyone who gets above 80 out of 100
gets an A grade. But since you set a really easy paper, everyone scored
above 80 and got the A grade.
Now there is nothing wrong in this kind of grading system. However,
using it, you can not differentiate between someone who got 81 and
someone who got 95 (as both would get the A grade).
To keep the comparison fair and keep the competitive spirit alive, a
bell curve is often used to evaluate performances (at least that’s how
it was when I was in college).
Using the bell curve approach, the marks of students are converted into percentiles that are then compared with each other.
Students getting higher marks are on the right side of the curve and
students getting low marks are on the left of the curve (with most of
the students being in the middle around mean score).
Now to understand bell curve, you need to know about two metrics:
Mean – the average value of all the data points
Standard Deviation – it shows how much the dataset
deviates from the mean of the dataset. For example, suppose you have a
group of 50 people, and you are recording their weight (in kgs). In this
dataset, the average weight is 60 kg, and the standard deviation is 4
kg. It means that 68% of the people’s weight is within 1 standard
deviation from the mean – which would be 56-64 kg. Similarly, 95% of the
people are within 2 standard deviation – which would be 52-68 Kgs.
When you have a dataset that is normally distributed, your bell curve will follow the below rules:
The center of the bell curve is the mean of the data point (also the highest point in the bell curve).
68.2% of the total data points lie in the range (Mean – Standard Deviation to Mean + Standard Deviation).
95.5% of the total data points lie in the range (Mean – 2*Standard Deviation to Mean + 2*Standard Deviation)
99.7% of the total data points lie in the range (Mean – 3*Standard Deviation to Mean + 3*Standard Deviation)
Here are the steps to create a bell curve for this dataset:
In cell A1 enter 35. This value can be calculated using Mean – 3* Standard Deviation (65-3*10).
In the cell below it enter 36 and create a series from 35 to 95
(where 95 is Mean + 3* Standard Deviation). You can do this quickly by
using the autofill option, or use the fill handle and drag it down to fill the cells.
In the cell adjacent to 35, enter the formula: =NORM.DIST(A1,65,10,FALSE)
Note that here I have hardcoded the value of mean and standard
deviation. You can also have these in cells and use the cell references
in the formula.
Again use the fill handle to quickly copy and paste the formula for all the cells.
Select the data set and go to Insert tab.
Insert the ‘Scatter with Smooth Lines’ chart.
This will give you a bell curve in Excel.
Now you can change the chart title and adjust the axis if you need.
Note that when you have a low standard deviation, you get a packed
slim bell curve, and when you have a high standard deviation, the bell
curve is wide and covers more area on the chart.
This kind of bell curve can be used to identify where a data point
lies in the chart. For example, in case a team is full of high
performers, when evaluated on a curve, despite being a high performer,
someone can get an average rating as he/she was in the middle of the
Note: In this blog post, I have discussed the concept of a bell
curve and how to create it in Excel. A statistician would be better
suited to talk about the efficacy of the bell curve and limitations
associated with it. I am more of an Excel guy and my involvement with
Bell curve has been limited to the calculations I did when I worked as a
Hope you found this tutorial useful!
Let me know your thoughts in the comments section.
The Six Sigma DMAIC
(Define, Measure, Analyze, Improve, Control) methodology can be thought
of as a roadmap for problem solving and product/process improvement.
Most companies begin implementing Six Sigma using the DMAIC methodology,
and later add the DFSS (Design for Six Sigma, also known as DMADV or
IDDOV) methodologies when the organizational culture and experience
level permits. You can read the main differences between DMAIC and
DMADV, but we’ll focus on the DMAIC in this article.
DMAIC methodology presented below may appear linear and explicitly
defined, it should be noted that an iterative approach may be
necessary – especially for Black Belts and Green Belts that are new to
the tools and techniques that make up DMAIC. For instance, you may find
that upon analyzing your data (Analyze phase) you did not gather enough
data to isolate the root cause of the problem. At this point, you may
iterate back to the Measure phase. In addition, prior knowledge of the
tools and techniques is necessary in determining which tools are useful
in each phase. Remember, the appropriate application of tools becomes
more critical for effectiveness than correctness, and you don’t need to
use all the tools all the time.
DMAIC Phase Steps
D – Define Phase: Define the project goals and customer (internal and external) deliverables.
Define Customers and Requirements (CTQs)Develop Problem Statement, Goals and BenefitsIdentify Champion, Process Owner and TeamDefine ResourcesEvaluate Key Organizational SupportDevelop Project Plan and MilestonesDevelop High Level Process Map
M – Measure Phase: Measure the process to determine current performance; quantify the problem.
Define Defect, Opportunity, Unit and MetricsDetailed Process Map of Appropriate AreasDevelop Data Collection PlanValidate the Measurement SystemCollect the DataBegin Developing Y=f(x) RelationshipDetermine Process Capability and Sigma Baseline
I – Improve Phase: Improve the process by eliminating defects.
Perform Design of ExperimentsDevelop Potential SolutionsDefine Operating Tolerances of Potential SystemAssess Failure Modes of Potential SolutionsValidate Potential Improvement by Pilot StudiesCorrect/Re-Evaluate Potential Solution
C – Control Phase: Control future process performance.
Define and Validate Monitoring and Control SystemDevelop Standards and ProceduresImplement Statistical Process ControlDetermine Process CapabilityDevelop Transfer Plan, Handoff to Process OwnerVerify Benefits, Cost Savings/Avoidance, Profit GrowthClose Project, Finalize DocumentationCommunicate to Business, Celebrate
you can see, the power of the Six Sigma DMAIC methodology lies in the
structure and the rigor. Of the hundreds of TQM tools that have been
developed over the years, the most important ones (described above) are
taught in detail by consultants to Black Belts and Master Black Belts.