问题如下：
Zimt AG wrote down the value of its inventory in 2007 and reversed the write-down in 2008. Compared to the results the company would have reported if the write-down had never occurred, Zimt’s reported 2008:(assume the companies use a periodic inventory system)
选项：
A.profit was overstated.
B.cash flow from operations was overstated.
C.year-end inventory balance was overstated.
解释：
A is correct.
The reversal of the write-down shifted cost of sales from 2008 to 2007. The 2007 cost of sales was higher because of the write-down, and the 2008 cost of sales was lower because of the reversal of the write-down. As a result, the reported 2008 profits were overstated. Inventory balance in 2008 is the same because the write-down and reversal cancel each other out. Cash flow from operations is not affected by the non-cash write-down, but the higher profits in 2008 likely resulted in higher taxes and thus lower cash flow from operations.
老师可不可以这么理解？
发生：第一年，理解为存货价格下降，COGS上升，利润下降；第二年，理解为存货价格上升，COGS下降，利润上升
未发生：第一年下降的部分就不会出现，第二年也就不会上升，所以相比来看，第二年的存货价格低于实际值，COGS高于实际值（actual），利润低于实际值
