The three pie charts below show the changes in annual spending by a particular UK schools in 1981 1991 and 2001 Summarize the information by selecting and reporting the main features and make comparisons where relevant

The pie charts delineate the changes which the whole expenditure per annum of a specific school in the UK underwent from 1981 to 2001 with a ten-year gap.
It is apparent that the first and the last rankings in the school’s spending remained stable, which went for teachers’ salaries and insurance, respectively. During the period, whilst the school expended more on insurance, furniture and equipment, the money allotted for the rest was partially cut down.
In 1981, the majority of the school’s money was allocated on teachers’ salaries, reflecting the most substantial percentage of 40%. Well over a quarter of the gross spending was for paying other workers. Following were expenses on resources, furniture and equipment with equal figures which summed up to three – quarters of the lion’s share. Seemingly the least attractive for the school was insurance with only a meager 2%.
After decades, a 5% increase took place in what showed to have remained the top priority, teachers’ salaries, whereas money allotment for other workers experienced a successive reduction, making it the third-ranking. Contrast was seen in resources, furniture and equipment, while expenses for the former, after a trivial rise to 20%, was cut down roughly a half, the latter went reversely to become the second most spending. Despite its upward trend, insurance remained at the lowest spot for which a marginal 8% was allocated.