These trends include population growth, initiation (the number that were initiated to heroin in a given year), and quitting (the number that quit using heroin). Relevant characteristics from data from the National Drug Strategy Household Survey, conducted in Australia in 1998, were summarized and extracted. A systematic procedure was devised to estimate historical trends from questions concerning past events. The results showed that the size of the heroin user population in Australia was in a sharp increase, especially from the early 1980's upwards. There was a short leveling-off period prior to 1990. Initiation was observed to be on a sharp increase. The latter trend was accompanied by a similar trend of quitting, perhaps indicating a relatively short heroin use career. A sharp decrease in both initiation and quitting was observed after 1990. The trend of the projected number of people that were initiated into heroin use peaked around the years 1977-80, 1987, and 1996-97. The trend of the projected number of people that quit the use of heroin peaked around the years 1980, 1988, and 1996-97. The trend of the projected numbers of people that were using heroin peaked around 1987 and 1997. This study demonstrates that even a static survey such as this can sometimes be used to extract historic (dynamic) trends of certain important variables. 8 figures, 4 tables, 17 references, 1 appendix