Averageif help

As shown in the sample provided I am averaging column C in column D by rolling week and in column E is the rolling year average taken from column C. These are then shown on dynamic graphs, I would like help if possible for columns D and E to show 0 from column C but not count them as part of the average as this would obviously give a false average.
Thanks in advance.

Lewster

Try...

=IFERROR(AVERAGEIFS($C$3:C3,$C$3:C3,">0",$C$3:C3,"<>"""),0)

Thank you John that seems to work magnificently.

Lewster