6  The correlation between real house prices and money growth in Japan was close to zero during the deflationary 1990s. assessed against historical experience. For equities, a stock's price-earnings ratio is a standard benchmark for assessing valuation.
In the late 1990s, the price-earnings ratio for U.S. equities especially in the high-tech area - soared to record levels, and the so-called equity risk premium narrowed to a historical low. There was a strong sense at the time that such elevated price levels were unusual, but there was no uniform consensus regarding whether or not they were sustainable.