Is there a way to combine Excel AVERAGEIF with AGGREGATE?

I have a spreadsheet with a col of phases (Phase 1, Phase 2, etc.) and col of percentage values for each phase. There are multiple of each phase and I want to calculate the average % for each phase.

I was using AVERAGEIF to calculate the average percentage for each Phase:

AVERAGEIF(Table1[PHASE], "Phase 1", Table1[PERCENTAGE]), etc.

That works fine. However, if any percentage values are N/A or errors, I don't want this to skew the calculations.

I read about AGGREGATE that ignores errors, but that only works with AVERAGE, not AVERAGEIF.
I also read about AVERAGEIF(A1:A5,">=0") and AVERAGEIFS for multiple error values, but this doesn't allow me to compare the PHASE col.

Any suggestions welcome.

For Microsoft 365, try the following formula...

=AVERAGE(FILTER(Table1[PERCENTAGE],(Table1[PHASE]="Phase 1")*(ISNUMBER(Table1[PERCENTAGE]))))

For earlier versions, try the following formula that needs to be confirmed with CONTROL+SHIFT+ENTER...

=AVERAGE(IF(Table1[PHASE]="Phase 1",IF(ISNUMBER(Table1[PERCENTAGE]),Table1[PERCENTAGE])))

However, you say that the column containing the percentage values contain error values, in addition to the text value "N/A". If the error values are the same type, let's say #DIV/0!, you can simply use the following formula instead...

=AVERAGEIFS(Table1[PERCENTAGE],Table1[PERCENTAGE],"<>#DIV/0!",Table1[PHASE],"Phase 1")

Change the error value for which to test accordingly.