What do "overall salary" for one fight consist of?

they earn all that money, yet so many top boxers get broke or fight for years after their prime because they didnt earn enough for hanging gloves up ones and for all. tax. promoter or maybe your not totaly on the point. I guess the promoter makes all the cash and the boxer gets a bit out of it. but aside floyd and the klits I doubt a lot of boxer make international tv money and all that...