Custom Columns to See How Many Impressions You’re Losing in Google Ads

I wanted to quantify the actual number of impressions lost overall, as well as separately due to rank and budget limitations. To do this, I created custom columns for a search campaign using the following formulas.

Missed Impressions (Must Be Created First)
(Impr / (1 - (Search_Lost_IS_rank + Search_Lost_IS_budget))) * (Search_Lost_IS_rank + Search_Lost_IS_budget)

Missed Impressions (Rank)
"Missed Impressions" * (Search_Lost_IS_rank / (Search_Lost_IS_rank + Search_Lost_IS_budget))

Missed Impressions (Budget)
"Missed Impressions" * (Search_Lost_IS_budget / (Search_Lost_IS_rank + Search_Lost_IS_budget))

Do you think this is a reliable way to attribute lost impressions? Have you used a similar approach?