The Pan American Judo Confederation (PJC) uses age Categories with specific minimum and maximum years of birth. 

In the USA, for 2009, these categories are referred to as:
Years of birth limits for 2009:

Intermediate 1: born in 1999 or 2000
Intermediate 2: born in 1997 or 1998
Juvenile A: born in 1995 or 1996
Juvenile B: born in 1993 or 1994

The Pan American Rosters are used for team selection in tournaments which restrict players' ages to the above listed birth years.

The Pan American Judo Confederation also conducts events with years of birth limited to 1990-1992 (in 2009).  However, USA Judo only maintains an open-ended roster called IJF Junior, limited to athletes born in 1990 or later.  When the IJF Junior roster is used to select athletes for PJC limited category, the athlete selected from the IJF Junior roster will be the highest ranked athlete who meets the year of birth criteria.  For example, if the #1 ranked athlete was born in 1993, and the #2 ranked athlete was born in 1992, then the athlete born in 1992 would be selected to attend the PJC event.