The art of city flipping?

[Zubbus]

I once took a city off a neighbor when my culture was 53% of that tile and he 47%. But then a lot of other cities had higher % of my culture and didn't flip. How does it work?

Thanks.

 

[cj7loop]

I think it has to do with the military units that the civ has in the city that could potentially flip. I'm not 100% sure on this though.

 

[henrebotha]

Every military unit stationed in the city reduces the chances of it flipping. If your rival has put a massive stack of soldiers in the city, you can forget about flipping it.