Calculate a single cell value with every row

[Ramesh1403]

 

I

 

have sales from 2018 to 2023, I need a measure to calculate 2018 day 1 sales price with total units , if 2018 sales price is not present, I need to calculate it with 2019 or else with 2020 day 1sales price * units. Currently my measure works row by row for sales price * units.please help me to update this .please find the attachment for detailed data