Programs, updated now for 2017, are ranked on their overall team strength, attrition rate, and swimmer improvement. A
small attrition rate, a high strength rating, and a high positive swimmer improvement percentage are good. A
program's ranking in all three is combined to find their overall rank.
Attrition is the percentage of non-seniors who do not return to swim the following year to that same program across the 2011-2017 timeframe.
Improvement is the average percentage change in times in a swimmer's top three events from one year to the next.
Strength is the team's overall strength in 2017.