From what we know when it comes to an yonko the Captain's crew each gets a 300 million bounty increase not including chopper (who is view as a pet) even if they didn't do anything in particular. But this is a one time thing once you reach yonko status.
Nami: 66 million to 366 million
Brook:83 million to 383 million
Franky:94 million to 394 million
Ussop: 200 million to 500 million
See the pattern here and most of these four didn't do anything in particular. Now for the rest of the crew.
Nico Robin:130 million to 930 million minus the 300 increase is only 630 million.
Sanji: 330 million to 1,032 billion minus 300 increase is only 732 million.
Zoro's and jinbe's you get the idea. So basically their actual bounties are the one's without the 300 million increase.
Nami: 66 million to 366 million
Brook:83 million to 383 million
Franky:94 million to 394 million
Ussop: 200 million to 500 million
See the pattern here and most of these four didn't do anything in particular. Now for the rest of the crew.
Nico Robin:130 million to 930 million minus the 300 increase is only 630 million.
Sanji: 330 million to 1,032 billion minus 300 increase is only 732 million.
Zoro's and jinbe's you get the idea. So basically their actual bounties are the one's without the 300 million increase.