depends on what you're trying to organize by. maybe 'birth month' is an important signifier.
* I was N years old on February 28th this year
* I will be N+1 years old on March 1st this year
Therefore:
* I was N-1 years old on February 28th last year
* I was N years old on March 1st last year
Perhaps the month is February and the non-leap year date is March 1st...
* I was N years old on February 28th this year
* I will be N+1 years old on March 1st this year
Therefore:
* I was N-1 years old on February 28th last year
* I was N years old on March 1st last year
Perhaps the month is February and the non-leap year date is March 1st...