The inaugural Ironman Lake Placid, in 1999, offered 120 Kona slots. Over time, the number of slots has been reduced significantly, to 100 by 2004, to 80 in 2005, and to 72 slots in 2009. Here's how the slots have been allocated by age group. [Also see 2004-2010 changes in IMLP Qualifying Times]
Note: In all years, 10% of slots were reserved for pros. In 2005 and 2007, Lake Placid hosted Male Pros only, and in 2006, Women Pros only.