Well I know partly why, my spreadsheet has about 180,000 rows. But that has not presented a problem for sorting or filtering.

But when I entered `=B2`

in cell C2 and stretched it down to the bottom, it took 10 minutes to calculate it. All the values in column B are simple integers. In fact, there are only about 5 different integers in that column. How could it possibly take that long to execute the simplest formula possible in Excel?

I'm running Excel 2013 on a brand new Alienware X51 computer, Intel i7-4790 @ 3.60GHz with 16 GB RAM, Windows 8.1 Examining my system performance, my CPU was at 20% or below during this "calculation," despite Excel claiming to be using all 8 cores. Why wouldn't it use more like 80% and get the job done 4x as fast? And why does it take so long to calculate the simplest formula anyway? It should take less than a second for ONE core!

Now I've done a `vlookup`

against another table with 57000 rows, and that finished within 15 seconds. How could a simple `=`

take so much longer?

And this ran instantly! `=IF(C2>3,E2+25,IF(C2>0,E2+5,E2-5))`

`=B2`

. Chose ahuman readableformat. Do a comparison and stress the differences. Probably eXcel is doing something on all the cells of the`B`

column, maybe it's only a check on formats, maybe it's changing it cell by cell, especially if it is not always the same. BTW, in my experience and IMHO,57k rowsandeXcelshould never be together... :)"...>57k rows and eXcel should never be together.":-) The worst is that it starts to work in an acceptable way and unpredictably (at least for me) it comes out with something like this. There is always a reason that maybe require more time to be solved then to start from scratch. Here I have the strong impression that eXcel starts to do smart operations on all the column`B`

or on all row`2`

cells. Now you can try to see if any of the other cells characteristics changes when you write`=B2`

. SaveAs in a human readable format that keeps formatting can be good for a comparison.2more comments