Excel SUMIFS

I declare victory!

=SUMIFS(massmurder!$H$2:$H$300,massmurder!$A$2:$A$300,"<>1*",massmurder!$A$2:$A$300,"<>2*",massmurder!K2:K300,"1")

This adds the H column (number dead) for every row that does not have a decade in column A (either 1* or 2*) and the corresponding weapon type column has a 1.

I have since realized that it is more meaningful to see what mass murders were committed with a single weapon.  This was bit more complicated.  Here is a typical formua:

AX
=SUMIFS(massmurder!$H$2:$H$1500,massmurder!$A$2:$A$1500,"<>1*",massmurder!$A$2:$A$1500,"<>2*",massmurder!K2:K1500,"=",massmurder!M2:M1500,"=",massmurder!N2:N1500,"=",massmurder!O2:O1500,"=",massmurder!P2:P1500,"=",massmurder!Q2:Q1500,"=",massmurder!R2:R1500,"=",massmurder!S2:S1500,"=",massmurder!T2:T1500,"=",massmurder!U2:U1500,"=",massmurder!V2:V1500,"=",massmurder!W2:W1500,"=",massmurder!X2:X1500,"=",massmurder!Y2:Y1500,"=",massmurder!Z2:Z1500,"=",massmurder!AA2:AA1500,"=",massmurder!AB2:AB1500,"=",massmurder!AC2:AC1500,"=")

And yes, I used emacs to construct all these equations.