Last week, I asked my email newsletter readers to submit “one data analysis problem you are struggling with”. We called it BYOD – Bring your own data. More than 100 people have emailed various interesting (and often very difficult) problems. This week (between 16th of February to 20th of February), let’s take a look at some of these problems and solve them.
This problem is sent by Fiona.
Situation: Our commissions are growing way faster than revenues
Let’s say you are looking revenues & sales commissions of your company for last few years. The data looks like this:
And you want to highlight the fact that commissions are growing faster than revenues.
So you plot YoY growth rates for revenues & commissions.
Problem: The chart of YoY growth rates is not convincing
Take a look at the chart. It doesn’t convey the message that we want. At best it says “revenue growth is less than commission growth”
How to convey the message “Commission growth is a problem for us”?
Option 1. Use indexed charts
When comparing 2 sets of values (that are in different order of magnitudes) over time, we can use indexed charts. They can tell the story of how the values have changed over time clearly.
Here is the indexed chart for our data:
How to create this chart?
Simple. Just follow below steps.
- Calculate index values. Assume first year value for each series as 100 (so revenues = 100, commissions=100 in year 2010)
- For next year, calculate the value as this year value / first year value
- Plot these indexed values on a line chart
- Adjust the line chart axis minimum to 1 (or 100%) if all values are >1
- You are done
Option 2. Visualize ‘for every % in revenue growth, commission grows by…”
We can calculate what is the change in commission growth rate for every % growth in revenues & plot this. This will depict the situation in a powerful & dramatic fashion, like this:
How to create this chart?
Even simpler. Just do these steps:
- Calculate % values by dividing YoY commission growth with YoY revenue growth
- Plot this as a column chart
- Draw a line at 100%
- Add a text box at this line and write “Ideal” on it.
- You are done.
Download Revenue vs. Commission growth charts
Click here to download the example workbook. Examine the formulas & chart settings to learn better.
How would you present this information?
My favorite approach is to use indexed charts. They are designed for this exact purpose.
What about you? How would you visualize this kind of information? What charting techniques will you use to get your message across? Please share your inputs in the comments section.
8 Responses to “Pivot Tables from large data-sets – 5 examples”
Do you have links to any sites that can provide free, large, test data sets. Both large in diversity and large in total number of rows.
Good question Ron. I suggest checking out kaggle.com, data.world or create your own with randbetween(). You can also get a complex business data-set from Microsoft Power BI website. It is contoso retail data.
Hi Chandoo,
I work with large data sets all the time (80-200MB files with 100Ks of rows and 20-40 columns) and I've taken a few steps to reduce the size (20-60MB) so they can better shared and work more quickly. These steps include: creating custom calculations in the pivot instead of having additional data columns, deleting the data tab and saving as an xlsb. I've even tried indexmatch instead of vlookup--although I'm not sure that saved much. Are there any other tricks to further reduce the file size? thanks, Steve
Hi Steve,
Good tips on how to reduce the file size and / or process time. Another thing I would definitely try is to use Data Model to load the data rather than keep it in the file. You would be,
1. connect to source data file thru Power Query
2. filter away any columns / rows that are not needed
3. load the data to model
4. make pivots from it
This would reduce the file size while providing all the answers you need.
Give it a try. See this video for some help - https://www.youtube.com/watch?v=5u7bpysO3FQ
Normally when Excel processes data it utilizes all four cores on a processor. Is it true that Excel reduces to only using two cores When calculating tables? Same issue if there were two cores present, it would reduce to one in a table?
I ask because, I have personally noticed when i use tables the data is much slower than if I would have filtered it. I like tables for obvious reasons when working with datasets. Is this true.
John:
I don't know if it is true that Excel Table processing only uses 2 threads/cores, but it is entirely possible. The program has to be enabled to handle multiple parallel threads. Excel Lists/Tables were added long ago, at a time when 2 processes was a reasonable upper limit. And, it could be that there simply is no way to program table processing to use more than 2 threads at a time...
When I've got a large data set, I will set my Excel priority to High thru Task Manager to allow it to use more available processing. Never use RealTime priority or you're completely locked up until Excel finishes.
That is a good tip Jen...