Index if in Excel

i know this should be straightforward enough but i cannot make my head get round this.

I am looking to Index if in excel and cannot do it. Basically, i have a working formula =INDEX(E:E,MATCH(A2,B:B,0)) What i need is it to have a blank and not a N/A when there is no data further on in A:A So, something like =IF(A2>0) THEN INDEX(E:E,MATCH(A2,B:B,0)) OTHERWISE "") would be perfect. I have tried =If(a2>0)--INDEX(E:E,MATCH(A2,B:B,0),""). This is all in Excel 2010. Many thanks in advance.