this is a formula to add data for mos NOV through APR
=VLOOKUP(B7,NOVTERM!$1:$65536,4,0)+VLOOKUP(B7,DECTERM!$1:$65536,4,0)+VLOOKUP(B7,JANTERM!$1:$65536,4,0)+VLOOKUP(B7,FEBTERM!$1:$65536,6,0)+VLOOKUP(B7,MARTERM!$1:$65536,6,0)+VLOOKUP(B7,APRTERM!$1:$65536,6,0)
I get data if all 6 months are...