Sorting Column Problem

For the file attached I am trying to sort by year first, then quarter. How do I go about doing this.

For instance it currently reads
2Q05
1Q06
4Q05
3Q05

Which is obviously incorrect I need it to read

2Q05
3Q05
4Q05
1Q06

My current fix was adding a new column labeled year. And then doing a sort by year and then by quarter. Is there a way to get this to sort out correctly without adding that extra column?
Many thanks