How many people play chess (in Australia, in 1980)

At the back of the book "Australian Chess into the 80's" by Ian Rogers, there was published a market research survey on how many people in Australia played chess. This survey was carried out in 1980, and in the absence on any further surveys, is still the 'gold standard' for estimating the number of players in this country (usually by the simple method of extrapolation).
Interestingly Reark only surveyed the 5 largest cities in the country (Sydney, Melbourne, Brisbane, Adelaide and Perth). They actually measured the "No. of Households wherein at least one person plays chess". Overall they found that 36% of housholds had at least one person who played chess, and concluded that the total number of people in Australia who could play chess was 2.24 million, which in 1980 was about 1 in 7 people.
In terms of percentages Melbourne came out on top with 42% of chessplayer households, while Brisbane came last with 25% (a point behind Perth). They also surveyed the age of players, although the results below may have now changed significantly.

• 0-12 years 11.9%
• 13-17 17.0%
• 18-29 36.5%
• 30-39 17.7%
• 40-59 13.8%
• 60+ 3%

In terms of gender percentage it was Male 74% Female 26%