The Impact of Age on Swimming Performance: What to Expect

Question
I was wondering how much age affects performance in the water. How much of a drop in swimming performance and endurance in longer events will be caused by getting older? As a competitive swimmer I would like to know what to expect as I get older, as I plan to continue swimming after college.

Answer
Greg--
It's hard to say how much times will drop.  The difference will probably be more noticable in the longer events, but if you watched or read about Dara Torres(41),you can definatly continue to improve or at least maintain performance if you are willing to work at it.
Hope this helps,
George