Crystal Reports Display Result of Stringvar in Report Header

Message

I am building each location in my report based on each "Location" group by using this formula.
whileprintingrecords;
stringvar LocationSet;
if LocationSet <> "" 
then LocationSet := LocationSet + ", ";
LocationSet := LocationSet + {Location};
I then display the array result of all the location in my report that resets when a new location comes along.  I can't get it to show in my report Header.  For instance, if the result of this was locationA, locationB, locationC then how can I get those to be included in my Header Text (ex. Results for locationA, locationB, locationC from Jan 1 - Feb 5).

Any ideas or thoughts are greatly appreciated.