Its homework time again.
This time, lets tackle an interesting & everyday problem.
Lets introduce our protagonist of the story – Jack.
Jack likes long road trips, smell of freshly brewed Colombian coffee, clicky-clack sound of his computer keyboard. He hates toll plazas (they slow him down) & Potassium permanganate.
And oh yes, Jack is obsessive about analyzing every little bit of data in his life.
That brings us to the recent road trip he took.
It was a total of 600 miles.
And Jack tracked the speed at which he was covering every 50 mile distance.
The data is neatly typed in to an Excel workbook (snapshot below), in the range A2:A13.
The problem – what is Jack’s average speed?
At the end of the trip, Jack wants to know what his average speed is.
But his Excel skills are mediocre. So he approached you, an awesome analyst in the making.
Your mission, if you choose to accept, is this:
Figure out which formula calculates average speed and post it in the comments section
So what are you waiting for. Open up Excel, solve the problem and share your answers here. Make Jack happy.
Click here to post your answer.
Want a clue?
There is no harme.An unusual formula works too.
Want more challenges?
If you are hungry for helping more poor Jacks, check out our Excel Challenges & Home work pages. Test your Excel skills, solve something tricky and feel awesome.
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...