I need help looking for a previous column value, i.e. user will input a time period and they will get the information for that period, but I also want to include the numbers from the previous period to compare. How will I go about this to make sure that every time a user changes the period it also gives the previous period numbers?

Thanks for the Help (I cant upload the excel file , I put the data below)

INPUT 2012Q4



This Quarter Last Quarter
Accounts 1,563
Volume 948
Pieces 839
Amount 837




2011Q4 2012Q1 2012Q2 2012Q3 2012Q4 2013Q1
Accounts 5,784 14,789 23,659 14,512 1,563 454,879
Volume 22 641 823 203 948 661
Pieces 461 692 424 101 839 910
Amount 844 785 765 610 837 921