I agree about it only being clear in hindsight. Part of the problem is that many people who write about bubbles have a vested interest one way or another (not

I agree about it only being clear in hindsight. Part of the problem is that many people who write about bubbles have a vested interest one way or another (not implying anything about the OP as I'm not familiar with the author). Real estate in Australia, where I live, is in a similar place right now. Lots of statistics show it is significantly overvalued; there are lots of counter-arguments why this level of house prices is "sustainable". "This time it's different," etc. Often the same statistics are used to support opposing conclusions by different authors. Unsurprisingly, most of the people who argue that housing prices are sustainable and Australia is not experiencing a real estate bubble also have an interest in selling houses. Arguably those on the other side have an interest in selling equities...