Warren Buffett, the stock god, once favored a market indicator that issued a warning to investors. This indicator is the ratio between the Wilshire 5000 Index, which represents the total market value of US stocks, and the Gross Domestic Product (GNP) of the United States. In 2001, Buffett said that this indicator "may be the best single standard to measure the valuation level at any particular moment." Buffett believed that if the ratio is too high, it means the greater the risk of foam in the market. Afterwards, this indicator was also known as the "Buffett Index". Due to the minimal actual difference between US GDP and GNP, GNP is gradually being replaced by GDP in calculations.