【答案解析】The pie charts compare the expenses of an average American household in 1970 and in 2004. The most significant change that can be seen was in the proportion that went towards paying the mortgage; and the other increase was in the outlay for childcare. In 1970 about a quarter of the household income was spent on mortgage payments whereas, by 2004, this had doubled to account for half of all expenditure. The 1970 family spent only one percent of income on childcare while the 2004 family allocated ten times more of the budget to this.
Expenditure on entertainment remained the same at 13% but the percentage spent on food halved from 25% to 12%; and 8% less of the total income was taken up by transport costs in 2004 (only 5%). Clothing costs consumed more of the budget in 1970, at 22%, but this fell to only 10% in 2004.
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