Here you go Bhutocracy
http://www.susancanthony.com/Resourc...hatwealth.html
That's the first relevant link I found doing a web search.
In the middle of that page it reads
Money reported in October of 1998 (p. 134) that 3/5 of lottery winners file bankruptcy within three years. They had more money but the same old bad habits.
3 out of 5 is 60%, and that's after THREE YEARS. The stat I quoted was from a book written in 2000 and it said 90% after 5 years, which isn't much of a reach from the stat above.
Just because you don't think its reasonable doesn't mean its not true.
The key to wealth and security is to spend less than you make and do it for a long time. What Red Shoe posted above about movie stars and such is very common. Income level has little to do with long term wealth and security if you constantly live above your means.