The third movies have always beaten the second by a decent amount. China is irrelevant here since none of the Star Wars movies, even The Force Awakens, have made much of an impact there at all. Since The Last Jedi made about 1.4B, Rise of Skywalker will be above that. Hence 1.5-2.0B. Unless, as some presume, The Last Jedi's backlash did in fact damage the franchise to an unprecedented extend. I'm banking on it mostly having been a vocal minority though. We'll see.