I have an excel spreadsheet that list's everyone out with their info in different columns. All I do is change the year and it calculates the age. Then I change the age on each person's label. The spreadsheet also helps keeping it easy by "sorting" by the column of month/day. Then all the list pops out in order of date, which helps if you are working with 50 birthdays & anniversaries.
Name Anniversary Birthday Year Age 2013
XX Nov 5 May 22 46
The labels sorta look like this
1stName LastName smaller font
19XX (XX YRS)