Conditional Formula Question

[Guest]

I have the following Columns (A and B) with binary output (1 and 0), such
that A and B would not both contain 1 but both could contain 0. What formula
would I use in column C that calculates % change between cells D1 and E1 only
when there has been a 1 in A and followed by a 1 in B. See example:
A B C
1 0 0.00%
1 0 0.00%
1 0 0.00%
0 0 0.00%
0 1 3.00%
0 1 0.00%
0 1 0.00%
1 0 0.00%
0 1 3.00%
0 1 0.00%

Thanks

 

[Fred Smith]

An If statement testing the two conditions should work:

=if(and(b2=1,a1=1),(e1-d1)/d1,0)