I have one query and need to write formula. I tried but if there is any other formula other than nested IF.

We have % for the each marks on performance based appraisal.
Marks 1-100 and
Percentage 0.2 to 20

if mark is 1 then increment will be 0.2%, if mark is 4 then increment will be 0.8%, if mark is 100 then increment will be 20%, the difference for each mark is 0.2%.

Now if i use IF formula, i have to write from 1 to 99, is there any other way to get the increment amount.

Please clarify at the earliest.