average if zero
 

I'm looking for a formula similar to the following, but one that works.

=average(if((A1:A4="Jones")+(C1:C4"0"),C1:C4))

Column A represent sales rep column, and I want to see the average sales for
all cells that have data entered in column C.

I've tried the ctrl+shift+enter, but it's still averaging with zeros, so
something is wrong with my formula.

Thank you.
--
Lori