sumif referencing a range based on a choice from a drop down

I have several different named ranges that I want to sum and the user chooses the range from a drop down box. I want to select the range based on that choice but when I reference the cell that contains the reference to the selected range I get a result ** 0, but no error. I realize I could use several nested "If" statements but I was looking for a more streamlined approach.

here is the formula:

=SUMIF(Regions,B4,worksheet!K13) K13 = the name ** the selected range.

if I put the name ** the range directly into the formula I get the correct result.

Thanks that works