At 09:39 AM 29/11/00 +1100, Dick Monks wrote: Dick >> It raises a whimsical question - how many people have lived in >> Australia since 1788? >Now thats a challenge I cant resist! >I reckon the number of people who have been permanent residents of Australia >since 1788 to be between 40 and 60 million, as follows:- You've got an interesting approach to the question. I couldn't think of where to begin to calculate it, but yours is a decent starting point. I knitted some numbers into Excel in front of TV during the news. "When Was That - Chronology of Australia" has estimated population for each year from 1788 to 1987. Total of the annual population for the first 200 years is about 863 million, but there's a few years missing for a few states in the colonial era. On a graph it's a set of fairly linear growth lines. There's two break points where the mean rate of population increase changes - early 1850 & about 1947. WW1 shows up as population decrease for a couple of years. 1912/13 has a very large increase - was there a heavily publicised migrant assistance scheme? The graph looks a bit more parabolic than exponential, but definitely not constant linear. The area under the graph is about half that under a straight line from zero to 20 million. You were a bit out with your estimate of 10,250,000 per year. The final population for 1987 is 16,248,800. Using the mean increase during 1982 to 1987 to extrapolate the population to the current year gives a population in 2000 of 19,323,879, and a total for 212 years of 1,094,944,480. Dividing that by 212 years gives approx 5,165,000 per year, about half your estimated average of 10,250,000. (This tallys with the visual estimate of the area under the two graphs.) I think 45 year average time in Australia is a bit high. In the colonial period many migrant adults lived only a couple of decades after arrival, and many children died before 10. WW1 shortened a lot of lives to less than 30. Post WW2 family migration includes a lot of grandparents. If average time in Australia was 35 it would mean that about 32 million people have lived in Australia. That's only about 65% more than currently live here. If time here was an average of 45 years then only 5 million more than the current population have lived here. By the way, is this really a valid method? Does the Bureau of Statistics have a web site? Gary =================== Gary Luke feraltek@zeta.org.au fax +61-2-9519-9907 Sydney, Australia