They don’t know and that’s why they’re not saying
The modern financial markets date from around 1870. During the first 120 years (1870–1990) the vaulation of stocks according to the Price/Earnings ratio varied in a range between 5 and 25, always over time reverting to the mean (15):
Since 1990 it seems as if we’re looking at a completely different thing:
When was the last time you noticed a news article discussing how the markets have gone haywire over the last 30 years? The financial analysts are probably in awe of the volatility and the extremes, but they have no explanations and so they “don’t go there.” For example: Vanguard is supposed to be forthright and conservative when it comes to offering guidance to customers. Yet I haven’t noticed them advising: “The stock market has become little more than a casino and momentum has driven valuations to a point where you all are nuts to keep investing in stocks.” Maybe I missed that memo.