We investigated the age distribution of autobiographical memories with the Galton-Crovitz method through the Internet. Almost 2000 participants in the United States and the Netherlands aged between 11 and 70 years participated. They were presented with 10 cue words, and were asked to recall and date autobiographical memories. We found strong evidence for a "reminiscence bump" in all participant groups at all ages, with peaks at ages 15--18 for men and 13--14 for women. This peak could be localised more precisely than in previous studies due to our large sample size. We were able to remove the forgetting effect from the empirical age distribution with a method that allows separate estimation of memory encoding and forgetting. American participants showed a tendency to report older memories than the Dutch. Age group and level of education did not influence the lifetime encoding function.