I am using the following formula in an Excel sheet, that performs the SUM in a range of cells from another sheet (ITEMS CONTROL):
=SUMIF('ITEMS CONTROL'!$B$2:$B$20000,B$1,'ITEMS CONTROL'!$C$2:$C$20000)
My issue is that when inserting rows in the sheet ITEMS CONTROL, the formula changes as follows:
After inserting 18 rows:
=SUMIF('ITEMS CONTROL'!$B$20:$B$20018,B$1,'ITEMS CONTROL'!$C$20:$C$20018)
After inserting another 18 rows:
=SUMIF('ITEMS CONTROL'!$B$38:$B$20036,B$1,'ITEMS CONTROL'!$C$38:$C$20036)
What should I change to keep always the original formula?