Problem with averageifs formula displaying #value!

Seems you are using a 2007+ version of excel.

In J3

=IFERROR(AVERAGEIFS(National!$E$4:$E$399,National!$D$4:$D$399,B3),0)-IFERROR(AVERAGEIFS(National!$E$4:$E$399,National!$D$4:$D$399,B3,National!$F$4:$F$399,$B$9),0)

Aah I see..

Try this

=IFERROR(AVERAGEIFS(National!$E$4:$E$399,National!$D$4:$D$399,B3,National!$F$4:$F$399,"<>"&$B$9),0)

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