SUMIFS()/12 or AVERAGEIFS() formula by DD from YYYY-MM-DD

Hi guys

I hope you are doing great

I would like to do a revenue projection in a chart based on date (day of the month) and revenue:

I need a formula to calculate the average revenue of each day of the month for the past 12 months (sheet 2) and then project on a chart what I should achieve.

For exemple, the first day of this month should be above $1,637.81

I can't change Sheet 2 as it's automatically generated by a script every day. So even if I change it today it will get overwritten the day after...

I'm sure there is an easy formula to take DD in sheet 1 column A in YYYY-MM-DD from sheet 2

Could you help me, please?