nobody knows that!!imagine that:every time when luffy wins an important pirates,government increase his bounty 3 times up(30.000=>100.000.000=>300.000.000.=>?)it's not that his bounty is 900.000.000!However if the government took the thriller barck arc into mind ,im sure that luffy's bounty will be much more than before!!! The government dose not need to look at the thriller bark arc into mind because thriller bark tuned out to be a ship run by a shichibukai in other words a pirate the government dose not care what happens between pirates