In Sheets, with monthly sales in C2:C4, type the formula in D2 that indexes each month to January = 100 when filled down.
In Sheets, with monthly sales in C2:C4, type the formula in D2 that indexes each month to January = 100 when filled down.
Answer
=C2/C2*100
The relative C2 walks down the months; the absolute C2 pins January as the base. D2 100, D3 159.0, D4 122.4.