sum vlookup until vlookup

This works with AND (:wink:
SUM(VLOOKUP($C4;‘01-11’.$C$4:$R$300;11;0);VLOOKUP($C4;‘22’.$C$4:$R$300;11;0))

This doesn’t work with TILL (:slight_smile:
SUM(VLOOKUP($C4;‘01-11’.$C$4:$R$300;11;0):VLOOKUP($C4;‘22’.$C$4:$R$300;11;0))

My goal is when I add a new tab between the specified tabs it is included in the sum.
Thanks