There are two types of bull markets. A "secular bull market" is a period in which the stock market index is continually reaching all-time highs with only brief periods of correction, as during the 1990s, and can last upwards of 15 years. A "cyclical bull market" is a period in which the stock market index is reaching 52-week or multi-year highs and may briefly peak at all-time highs before a rapid decline, as in the early 1970s. It usually occurs within relatively longer bear markets and lasts about three years.