Today we will learn how to calculate weighted average in Excel with percentages.
What is weighted average ?
Weighted average or weighted mean is defined as [from wikipedia],
The weighted mean is similar to an arithmetic mean …, where instead of each of the data points contributing equally to the final average, some data points contribute more than others.
…If all the weights are equal, then the weighted mean is the same as the arithmetic mean.
Why should you calculate weighted average?
Well, it is because, in some situations normal averages give in-correct picture. For eg. assume you are the CEO of ACME Widgets co.. Now you are looking annual salary report and being the numbers-gal you are, you wanted to find-out the average salary of your employees. You asked each department head to give you the average salary of that department to you. Here are the numbers,
Now, the average salary seems to be $ 330,000 [total all of all salaries by 5, (55000+65000+75000+120000+1200000)/5 ].
You are a happy boss to find that your employees are making $330k per year.
Except, you are wrong. You have not considered the number of employees in each department before calculating the average. So, the correct average would be $76k as shown above.
How to Calculate Weighted Average in Excel with Percentages
There is no built-in formula in Excel to calculate weighted averages. However, there is an easy fix to that. You can use SUMPRODUCT formula. By definition, SUMPRODUCT formula takes 2 or more lists of numbers and returns the sum of product of corresponding values. [related: Excel SUMPRODUCT Formula – what is it and how to use it?]
So, if you have values in B4:B8 and the corresponding weights in C4:C8, you can use SUMPRODUCT like this to get weighted average.
=SUMPRODUCT(B4:B8, C4:C8)
Caution: However, the above method works only if C4:C8 contains weights in percentages(%) totaling to 100%.
WAvg Formula Pattern (use this with your data)
=SUMPRODUCT(<your values>, <your weights>)What if my percentage weights don’t add up to 100%?
May be your weights are more than 100 percent. Or may be they are less than 100 percent. In both cases, you can use the below formula variation.
=SUMPRODUCT(B15:B19, C15:C19) / SUM(C15:C19)
The idea is to divide the total of weights with the SUMPRODUCT result so that we can adjust Weighted Average as the weights don’t add up to 100 percent.
WAvg Formula Pattern when weights don’t add up to 100 percent
=SUMPRODUCT(<your values>, <your weights>) / SUM(<your weights>)Weighted Average when you have counts instead of weights:
If you have count of observations instead of weights, you can still use the SUMPRODUCT formula to calculate weighted average in Excel.
Here is the formula for above example:
=SUMPRODUCT(B26:B30, C26:C30) / SUM(C26:C30)
Notice that this formula is same as the formula for weighted average with weights not adding up to 100 percent.
WAvg Formula Pattern when you have counts instead of weights
=SUMPRODUCT(<your values>, <your counts>) / SUM(<your counts>)Weighted Average with Extra Conditions
Let’s say you have city wise observations and weights. And you want to calculate the weighted average, only for Boston values. In this case, you can use a variation of the formula like below:
=SUMPRODUCT((C5:C16)*(B5:B16=F5),D5:D16)/SUMIFS(D5:D16,B5:B16,F5)
How does this formula work?
- SUMPRODUCT calculates the total value for BOSTON by summing up C5:C16 (value column) where B5:B16 is Boston (highlighted portion of the formula) and multiplies that with the counts.
- So in the above example, this will just give us the total of Boston – ie 218,600
- We then divide this with the total count of Boston (using the SUMIFS formula) – ie 400
- This results in the weighted average for Boston values alone – ie 546.50
For more information on how the conditions work inside SUMPRODUCT formula, please read this article.
Download Weighted Average Calculation Example Workbook:
In this workbook, you can find 4 examples on how to to calculate weighted average in excel. Go ahead and download it to understand the formulas better.
Weighted Average in Excel – Formula Explained
Here is a video with Weighted Average formula explained. Please watch it below to learn more. Alternatively, head to my YouTube page to see the weighted averages in Excel video.
In Conclusion
Weighted averages are a great way to explain data and every data analyst should know how and when to use them with their data. Apart from Weighted Average, I suggest learning how to use moving average and average of top n values. These will help you explain the data and trends to your audience better.
Do you use Weighted Mean / Weighted Average?
What do you use it for? What kind of challenges you face? Do you apply any tweaks to weighted average calculations? Please share your ideas / tips using comments.
28 Responses to “Team To Do Lists – Project Tracking Tools using Excel [Part 2 of 6]”
[...] & tracking a project plan using Gantt Charts Team To Do Lists - Project Tracking Tools Part 3: Preparing a project time line [upcoming] Part 4: Time sheets and Resource management [...]
the templates are great (I bought the combo).
What I'm missing is a way to have the project gantt chart and reporting with the data per resource, in such a way that I can also show the occupation per resource on an extended gantt chart.
So with hours entered per person per project or sub-activity, to show a gantt chart of how many hours/days a person spent on which project (or plans to spend).
[...] from: Team To Do Lists - Project Tracking Tools using Excel [Part 2 of 6] 25 Jun 09 | [...]
Hi Chandoo,
Funny I have a post on the value of MS project lined up which I will post when the current monster project I'm working on finishes and I get some free time!
I'm not sure this would help with any of the projects I've worked on, closing down a to do list seems like more effort than it's worth, but it might be useful for some things. I guessing it doesn't, but does the time stamp not update when you recalculate the work book?
keep up the good work!
Ross
@Ross.. Thanks for sharing your ideas... I think to do lists are a great way to keep up with project activities and ensure accountability from individual team members, when they are implemented right.
"I guessing it doesn’t, but does the time stamp not update when you recalculate the work book?"
Your guess is right. When you change the calculation mode to "iterative", excel takes care of the nittygritties and retains older values in circular references in formulas.
[...] Project Management in Excel [New Series] - Gantt Charts | To Do Lists [...]
[...] & tracking a project plan using Gantt Charts Team To Do Lists - Project Tracking Tools Project Status Reporting - Create a Timeline to display milestones Part 4: Time sheets and Resource [...]
Hi Chandoo,
The template give me lot of convenience to monitor the thing to do. It simple. Thank You
[...] & tracking a project plan using Gantt Charts Team To Do Lists - Project Tracking Tools Project Status Reporting - Create a Timeline to display milestones Part 4: Time sheets and Resource [...]
[...] make sure you have read the first 4 parts of the series - Making gantt charts [project planning], team todo lists [project tracking], project time lines chart [reporting] and Timesheets and Resource Management using Excel. Also [...]
Chandoo,
I really do not see any befit to this function in Excel unless it was somehow tied into some other chart. That is say a scheduled activities % complete is based on the to-do list.
The only way this chart would be useful is if no one was assigned none dependent task that could be done by anyone. The cases were both of these conditions are true are so few and far between it really makes this chart worthless.
@Brian... Once you have a todo list up and running, it is easy to get metrics out of it. I didnt propose it as it might look a bit too micro-management-ish.
I am able to understand what you meant by "The only way this chart would be useful is if no one was assigned none dependent task that could be done by anyone. The cases were both of these conditions are true are so few and far between it really makes this chart worthless."
Can you explain?
"Chandoo"
What I mean is this. Lets say you have 10 task which are part of one activity/WBS that is in your schedule. One there are very few cases were many people would be assigned to complete this one scheduled activity with no direction being given who should what of the 10 task. It is poor management, and the task 90% of the time would not get done in a timely manner if say 4 people were responsible. Secondly, you are assuming all 10 task are independent of each other. You might need to do task 1 thru 3 before you can do task 4, and to do task 7 you might need to do 4 and 6. Thirdly, the time it would take to compile and then fill out the to-do-list even in limited applications is really not worth it.
I just see almost no applications why a team would need to inform others separate from the schedule that they have completed a task on a to-do list unless anyone of the 4 people could of completed that task.
My point is, there might be a few very limited applications for this type of list but this list would be worthless as a Project Management tool in every other case.
However, change this from a to-do-list to a document change log and it is perfect. Instead of to-do it is the documents name or summary of what changed in the document. The person is who edited the document, and the time stamp is when they checked it in. But I do not know why you would use excel when there is free software you can use commercially that is 10 times better that does document management.
I think using excel to do Project Management over a real Project Management application is a bad idea. Unless you are running a very small, simple project, the time and effort is a lot more to use excel compared to the cost of the Project Management software.
This comes back to my point, I love your site, however, just because you can do something in excel does not mean you should do it. To often the time it takes to use excel is wasted 10 times over from the cost of doing it in an application designed to for the specific application.
@Brian: The todo list mentioned here is meant to keep track of all the tasks for which detailed planning is not necessary but some sort of tracking is needed. These are not be confused with project activities (a la gantt chart).
I like your suggestion about using this as a document tracker. Pretty cool use.
Coming to your point about excel as a real project management tool, well, I have my views, but in a serious project environment, it would surely payoff to have a dedicated project management application.
[...] & tracking a project plan using Gantt Charts Team To Do Lists – Project Tracking Tools Project Status Reporting – Create a Timeline to display milestones Time sheets and Resource [...]
Chandoo,
Wonder how the timestamp column will maintain its previous data. Both Today() and Now() functions will update as and when the next timestamp happens.
[...] Preparing & tracking a project plan using Gantt Charts Part2: Team To Do Lists – Project Tracking Tools Part3: Project Status Reporting – Create a Timeline to display milestones Part4: Time sheets and [...]
I've combined this with the issue tracker since I like the automatic date stamp, but one thing I'm noticing is that I can't replicate the chart that goes along with the issue tracker because the cells that are referenced have the formula that inserts the time stamp instead of a the actual date value. All the dates of the last 30 days display 0 when they should have a value.
Is there a way around this?
I have edited the chart so that my team members can update the percentage completion of the assigned tasks. When the cell is updated, i would like the time stamp to update. How would I manipulate the formula to update whenever the drop-down list is changed?
[...] … ??? To Do List [...]
Excel is great however sometimes you need to get a better idea of what tasks each person on your team is working on at any given time. We've developed a web app that can do just that! Each person has a list of tasks, listed in the order they have to complete them.
HII,
I want to expand the database through excel where i am working on 11 cities as of now and i want to expand it upto 50 cities and hence forth the data related to it will also expand so i want to make it precise where i can get updates also that this work is required to be done at that particular day or date
Thanks for making all of this information available for free. I am currently using excel to track everything for the first time. I later plan to output our information here with a more visual presentation. Wish me luck!
Can some one point me out to some additional direction on the "Who Finished it?" column? Something more 'basic' for a newbie excel guy? lol I got everything else working on this tutorial but that column. I can't seem to recreate it and I know a lot of it is due to lack of knowledge with VB code. I'd like to recreate this column very much 🙁
Dear Chandoo,
Thanks for the team to do list, kindly let me know how to set the column who " finished it " from another work sheet
Hi Chandoo,
Unable to download it - can you please check the link and confirm.
Great inhisgt! That's the answer we've been looking for.
Hi Team,
I know u all are the best programmers in the world!!! that's I am here to rectify my issues. here is my question please ans me as soon as possible before 8-3-2017 its really urgent.
I have a project named the production tracker.
1) I require the user form which shows the names of the Associates which are linked to the different tracks. when the user is selected the particular track related details and dropdowns should appear.
2) I need to track the associate needs how much of the time to complete the particular task. with start stop and pause and resume timer.
3) It should display the daily count of the production and save the data to the another Excel file.
this production tracker should save all the data no matter how many people logs in into it.
Please help me for this it will be very appreciated.
you can directly email me on my mail ID: tusharkch694@gmail.com