What is an easy way to calculate YTD sales for last year for the same months that have sales this year? In the example below, I want a formula that will determine that we are 4 months into this year, and only add the first 4 months of last year so that we have a YTD comparison. In this example, the 272 is what I am looking for but I don't want to have to update the formula each month. Any help is appreciated!
<tbody>
</tbody>
Last Year | This Year | |
January | 34 | 45 |
February | 21 | 36 |
March | 72 | 45 |
April | 145 | 21 |
May | 24 | |
June | 36 | |
July | 73 | |
August | 51 | |
September | 18 | |
October | 12 | |
November | 68 | |
December | 99 | |
TOTAL | 653 | 147 |
Comparative | 272 | 147 |
<tbody>
</tbody>