Simplification of IF formula

I have little complex formula in the attached file that i want to make it simple, kindly assist.

Thanks
Attachment 68

Attachment 67

Hi,

May be..

=IFERROR(SUMPRODUCT(--(A36>=A12:A33),C12:C33)+(INDEX(C12:C33,MATCH(A36,A 12:A33)+1)/(INDEX(A12:A33,MATCH(A36,A12:A33)+1)-INDEX(A12:A33,MATCH(A36,A12:A33)))*(A36-INDEX(A12:A33,MATCH(A36,A12:A33)))),SUM(C12:C33))

HTH

Thanks, it works, anyother simpler version...

Hello, Try this,

=IFERROR(SUMIF(A12:A33,"<="&A36,C12:C33)+(INDEX(C1 2:C33,MATCH(A36,A12:A33,1)+1)/(INDEX(A12:A33,MATCH(A36,A12:A33,1)+1)-LOOKUP(A36,A12:A33)))*(A36-LOOKUP(A36,A12:A33)),SUM(C12:C33))

thanks,