Try this in "Summary" sheet column C (Assumes data in "Data" starts in row 2 and ends in row 5:

=SUM(IF((MONTH(Data!$A$2:$A$5)=MONTH(E2))*(YEAR(E2)=YEAR(Data!$A$2:$A$5))*(Data!$D$2:$D$5>=0)*(Data!$D$2:$D$5<=2),1))

Use CNTRL-SHIFT-ENTER and fill down.

- Clay Ver Valen
Excel Help