Using Winter Season as X axis marks

Hi,

I'm developing an expenditure graph that tracks funds against the winter seasons for several years. My problem is that excel can't seem to interperet the way I enter the seasons. For example, my intervals are 2002-2003, 2003-2004, (since winter crosses over into the new year). I've tried to create a custom formatting reference, but it wants to reformat to a date as if it were a code.
Any suggestions?

Change "-" into " - ".