NO.PZ2023010401000113
问题如下：
If relative to prior values of their respective indicators, the inventory–sales ratio has risen, unit labor cost is stable, and real personal income has decreased, it is most likely that a peak in the business cycle:选项：
A.has occurred. B.is just about to occur. C.will occur sometime into the future.解释：
Both inventory–sales and unit labor costs are lagging indicators that decline somewhat after a peak. Real personal income is a coincident indicator that by its decline shows a slowdown in business activity.
中文解析：
"库存销售"和"单位劳动力成本"都是滞后指标，它们在经济达到峰值后有所下降。“实际个人收入”则是一个同步的指标，它的下降表明商业活动放缓。
为何Aggregate real perisonal income是同步指标，change in unit labor cost是滞后指标，同样都涉及收入
