The bar chart illustrates how many people were imprisoned in five different countries over a period of 50 years.

The given bar chart illustrates the imprisonment levels of 5 specific countries from 1930 to 1980. In general, it can be clearly seen that the number of inmates in US and Canada was the highest. Furthermore, there were 3 certain nation witnessing the upward trend in imprisonment rate after 50 years, namely Great Britain, New Zealand and America. Initially, 120, 000 people in Canada was in the jail in 1930, which was the highest rate in this year. After slight fluctuation during 50-year period, this fingure led the rank at nearly 140, 000 prisoners in 1980, by contrast, there was a unremarkable fall of imprisonment level in Canada from 100, 000 to more than 80, 000 people. Besides that, in the year 1930, the number of inmates in Great Britain registed the lowest at around 30, 000 and maintained unchanged to 1940. After that, this fingure rose significantly, and then reached more than 80, 000 imprisons. In term of Australia, after hitting the bottom in 1940 from nearly 70, 000 to around 50, 000, this rate increased steadily and registed the nearly same figure, compared with data on imprisons in Great Brittain. Regarding the imprisonment level in New Zealand, they went up and down in this period and stopped at approximately 50, 000.