The given bar graph demonstrates the number of sales of four types of reading materials during the period from 2002 to 2012. While the leading genre is history books, the others show different figures over the 10 year period.
As shown in the chart, history books had the highest amount of sales, unlike the hobby books, which were emphasized by a small group of people. Sales of that category never rose over one thousand and stayed stable through the years. In contrast to the history books, which had over 4000 purchases at the start. By 2008, this mark had rapidly increased to the highest number of 10000 purchases. However, in 2010 it had fallen to 8000 sales and remained still.
Meanwhile, art book sales grew equally to entertainment books, with only slight differences. In 2002, the number of sales reached slightly less than two thousand, before the sales of those categories slowly rose in 2006, reaching 3000. Also, in 2010, the figure for entertainment books remained stable for the next few years, while art books grew significantly in popularity to make 4000 sales.