=HLOOKUP("tot_prem",'Column Output'!A:BW,8,FALSE)/1000+HLOOKUP("tot_prem",'Column Output'!A:BW,9,FALSE)/1000+HLOOKUP("tot_prem",'Column Output'!A:BW,10,FALSE)/1000+HLOOKUP("tot_prem",'Column Output'!A:BW,11,FALSE)/1000+HLOOKUP("tot_prem",'Column Output'!A:BW,12,FALSE)/1000+HLOOKUP("tot_prem",'Column Output'!A:BW,13,FALSE)/1000+HLOOKUP("tot_prem",'Column Output'!A:BW,14,FALSE)/1000+HLOOKUP("tot_prem",'Column Output'!A:BW,15,FALSE)/1000+HLOOKUP("tot_prem",'Column Output'!A:BW,16,FALSE)/1000+HLOOKUP("tot_prem",'Column Output'!A:BW,17,FALSE)/1000+HLOOKUP("tot_prem",'Column Output'!A:BW,18,FALSE)/1000+HLOOKUP("tot_prem",'Column Output'!A:BW,19,FALSE)/1000