Missing percentages in a range

[philzar]

I have the following info:
A timeline in the form of a percentage - 0-100% (0, 1, 2, ... 100%. Let's name this t and p=percentage progress
So: at t-40 p=0, t-45 p=0,56%, t-50 p=1,68%, t-55 p=5,94%, t-60 p=12,61%, t-65 p=21,31%, t-70 p=32,4% and it continues to t-100.
What is excel formula to calculate the missing percetages for each increment of t. Therefore, what is the % for t-1, t-2, t-3, t-4 and t-6, t-7 .......
Kind regards
Philzar