開頭

What a thought-provoking and illuminating chart it is! As is apparently depicted in the chart, it is obvious that（內(nèi)容）soared from（數(shù)據(jù)）in（年份） to（數(shù)據(jù)） in（年份）, While, as a sharp contrast, （內(nèi)容）decreased from（數(shù)據(jù)）in（年份） to（數(shù)據(jù)） in（年份）.In addition ,（內(nèi)容）was almost the same in（年份）and（年份）./（there was only a slow increase from（數(shù)據(jù)）in（年份） to（數(shù)據(jù)） in（年份））

過渡段

Why does this phenomenon revealed in the chart above appear? Several reasons accounting for the situation can be what follows. To begin with ,I am strongly convinced that this is partly duo to the fact that（原因一）, In addition, this is partly because ，（原因二）, Last but not least,this is partly because（原因三）. Maybe there are some other reasons bring about this phenomenon. But it is generally believed that the above mentioned reasons are commonly acceptable.

結尾

From the analyses made above , we may come to the conclusion that（結論）. I am sure my opinion is both sound and well-grounded.