Third time is a charm. Here is article #3 where we unearth the history of bear and bull markets. By now you know that a bear market is when there is a 20% drop in stocks from a previous high. And the commonly accepted definition of a bull market is when stock prices rise by 20% after two declines of 20% each. (Fingers crossed!) Although stocks rise and fall in the short term, they’ve historically tended to reward investors over longer periods of time. That's why we invest. In this latest post from AssetMark, you'll see that bull markets have historically lasted longer than bear markets. History of Bull and Bear Markets.