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The bar chart draws a comparison between the number of prisoners in Great Britain , Australia , New Zealand, United States and Canada from 1930 to 1980.

Overall, the propotion of people in prison in 5 countries fluctuated. The figure for Canada was the highest almost all the time surveyed and Great Britain had the least , however, after 50 years the figure for prisoners decreased in America and Canada was the highest almost the time surveyed.

It is clearly seen that the United States had the highest number of inmates. Also, Britain had the lowest figure in 4 out of 6 years. In 1930, the number of prisoners in the United States was the highest, with 120 thousand prisoners, then this number increased significantly to reach a peak of 140 thousand in 1980. By contrast, Britain had the lowest figure of prisoners until 1970, then the figure jumped suddenly to reach 90 thousand.

Canada had the highest number of imprisonment in 1930 and 1960 with nearly 140 thousand people in each year.In 1970 the number of prisoners in Great Britain, New Zealand and Australia was same, about 70 thousand people. In 1980, 50 thousands of people in New Zealand were put in prison which was the lowest figure in this year.