call macro from combo box

I had some help earlier; where I'm trying to have a macro run once its selected from a combo box - and this code works well:

 Private Sub ComboBox1_Change()

Select Case ComboBox1.Value
   Case 1
     Call Macro1
   Case 2
     Call Macro2
   Case 3
     Call Macro3
   Case 4
     Call Macro4
End Select

End Sub

What I'm getting hung up on is the macros only run if its numbers populating the combo box, say if my linked cells read 1-7 that would work but Sunday-Saturday does nothing. Is there something in the properties menu or in the coding that can read numbers but not characters? Thank you