=PERCENTILE(B:B,1-PERCENTRANK(A:A,D2,30))

with data in first two columns eg D2=27.662 gives 0.846

"Harish" wrote in message
...
Hi,

I have a table:

A SHGC
0 0.86
40 0.84
50 0.82
60 0.78
70 0.67
80 0.42

For example, I want to find the SHGC value for the corresponding A
value of 27.662, How can i use a function in excel to do that
interpolation?