Well, the history thinks differently, the penny has been "changed" 5 times in the last centure that's 20 years on average. And the last change happened in 1982 (28 years from now) well above the average time period and is the third longest survival period for a penny ever.<p><a href="http://en.wikipedia.org/wiki/Penny_%28United_States_coin%29#History_of_composition" rel="nofollow">http://en.wikipedia.org/wiki/Penny_%28United_States_coin%29#...</a>