We investigate whether differences in individuals’ experiences of macro-economic shocks affect longterm risk attitudes, as is often suggested for the generation that experienced the Great Depression. Using data from the Survey of Consumer Finances from 1964-2004, we find that birth-cohorts that have experienced high stock market returns throughout their life are more likely to be stock market participants, and, if they participate, invest a higher fraction of liquid wealth in stocks. They also report lower aversion to risk. These results are estimated controlling for age effects, year effects, and a broad set of household characteristics. Our estimates indicate that stock market returns early in life affect risktaking several decades later. However, more recent returns have a stronger effect, which fades away slowly as time progresses. Thus, the experience of risky asset payoffs over the course of an individuals’ life affects subsequent risk-taking. Our results explain, for example, the relatively low rates of stock market participation among young households in the early 1980s (following the disappointing stock market returns in the 1970s depression) and the relatively high participation rates of young investors in the late 1990s (following the boom years in the 1990s).

We examine changes in the stock trading behavior and investment performance of 1,607 investors who switch from phone based to online trading during the period 1992 to 1995. We document that young men who are active traders with high incomes and a preference for investing in small growth stocks with high market risk are more likely to switch to online trading. We also find that those who switch to online trading experience unusually strong performance prior to going online, beating the market by more than two percent annually. After going online, they trade more actively, more speculatively, and less profitably than before-- lagging the market by more than three percent annually. A rational response to reductions in market frictions (lower trading costs, improved execution speed, and greater ease of access) does not explain these findings. The increase in trading and reduction in performance of online investors can be explained by overconfidence augmented by self-attribution bias, the illusion of knowledge, and the illusion of control.