The best suggestion I can come up with for now is to specify the format MONYY7.
Do you want to do something with the variable that has month/year value? Or do you just want to display it?
I want to say you can't make a variable that has just the month/year value, because SAS wouldn't understand it. eg 5/25/2012 has the value 19138 in SAS, while 5/24/2012 has the value 19137. Can't just say 5/2012. But there's ways to work around this.
Why can't you just pull the month and year and work with those variables jointly?