Formula for percentage of principal payment

[moldysp]

holla guys, I want to make a formula for the percentage of principal payment items whose cumulative weight value is at least 80% (eighty percent) of the entire value of the work,
calculated starting from the payment item with the largest weight value

is there a formula I can use

 

[moldysp]

holla guys, I want to make a formula for the percentage of principal payment items whose cumulative weight value is at least 80% (eighty percent) of the entire value of the work,
calculated starting from the payment item with the largest weight value

is there a formula I can use
View attachment 104353

I want to use a formula that only calculates the highest percentage value when added up to 80%