The three pie charts below show the changes in annual spending by a particular UK school in 1981, 1991 and 2001. v.1

A glance at the three given graphs reveals some differences among the expenditures per year of a British school in a period of three years: 1981, 1991, 2001. Overall, it can be seen that there are many trends that are obviously illustrated in those charts: upward, downward and both upward and downward. The changes of those features can be divided into two main groups on account of their trends: single trend and couple trends group. Starting with the first group, insurance and other workers’ salaries, in 1981, the insurance only took two percent of the total, however, in twenty years later, the number experienced a considerable growth of six percent to eight percent. Unlike the insurance, the salaries of other workers witnessed a respective drop from approximately thirty percent to a mere fifteen percent in about twenty years. Moving on to the second group, we can see that both teachers-salaries’ and resources’ proportions significantly fluctuated. In the first ten years of the period, the numbers rose five and ten percent to reach fifty and twenty percent, however, slipped dramatically in the next years from fifty to forty-five and from twenty to a mere nine percent. In contrast, furniture and equipment spending first experienced a decrease and then quickly climbed from five percent in 1991 to twenty percent, a growth of eighteen percent. It is interesting to note that through approximately twenty years, the total spending on different things of this UK school changed considerably.