I mean i guess it is affected by the PR slightly, but not to the level you're suggesting.
On a week where both players play for the US once: 165k
When only one plays once: 130-140k
When one plays twice and one plays one: 230k
No one plays: 90k
i.e. it makes a massive difference if they play or not, it's the no1 factor. I'm also guessing the 'home' factor plays a large part too.