You could use something like (see attachment as Pound sign does not copy well here):
Formula:
=SUMPRODUCT(Table2119123[@[L10]:[L30]],--SUBSTITUTE(Table2119123[[#Headers],[L10]:[L30]],"L",""))
=SUM(B3:B6)*SUBSTITUTE(Table2119123[[#Headers],[L10]],"L","")
Of course you could work on standard ranges like B$2:C$2 instead of Table2119123[[#Headers],[L10]:[L30]]
But general concept would be to use just numbers (10 and 30) in header and only format it as currency or accounting, to see pound sign there, for instance in such a way, as I did with results of the formulas.
Bookmarks