Freezing The Formula After Certain Time / Formula Has Been Satisfied?

I am trying to create a graph of my data at the end of each month. The graph will show a count of the number of instances of each category in the data.

For example:

A1 =TODAY()B1 =MONTH(A1)

Column A from A3 down = 1,2,3,4,W,H,L
Column I between I2 and I140 = multiple instances of 1,2,3,4,W,H,L

July
=IF($B$1=7,(COUNTIF($I$2:$I$140,$A3)),"0")
=IF($B$1=7,(COUNTIF($I$2:$I$140,$A4)),"0")
=IF($B$1=7,(COUNTIF($I$2:$I$140,$A5)),"0")
=IF($B$1=7,(COUNTIF($I$2:$I$140,$A6)),"0")
=IF($B$1=7,(COUNTIF($I$2:$I$140,$A7)),"0")
=IF($B$1=7,(COUNTIF($I$2:$I$140,$A8)),"0")
=IF($B$1=7,(COUNTIF($I$2:$I$140,$A9)),"0")
=IF($B$1=7,(COUNTIF($I$2:$I$140,$A10)),"0")

My problem is that when it comes around to August or the next month, I want the final count of July to be fixed/frozen so it won't change from the 1st of the month. I can then use the July column's data for my graph.

Can a formula convert itself into a value or freeze itself after certain criteria has been fulfilled?