It i obviou in the graphic/table that the rate/number/amount of Y ha undergone dramatic change. It ha gone up/grown/fallen/dropped coniderably in recent year (a X varie). At the point of X1, Y reache it peak value of …(多少).
What i the reaon for thi change? Mainly there are … (多少) reaon behind the ituation reflected in the graphic/table. Firt of all, …(第一个原因). More importantly, …(第二个原因). Mot important of all, …(第三个原因).
From the above dicuion, we have enough reaon to predict what will happen in the near future. The trend decribed in the graphic/table will continue for quite a long time (if neceary meaure are not taken括号里的使用于那些不太好的变化趋势).