What percent of CPP-D will CPP-R be?

When my CPP-D converts to regular CPP, can anyone guess what % it will be?
My current CPP-D divided by what Service Canada estimates my CPP-R will be is 73%.
Is 73% a common percent when it changes over?

I got an estimate so mine will be about 80% They actually told me approx. how much I would get a month.

They told that when your CPP-D converts to CPP, you get 80% of the CPP-D?

That is what mine worked out to re: %.