它展示了平均的回复性质，但在1999年却是极大的。

It displays mean reverting properties but is unbounded as of 1999.

youdao

所以即便我们睡着了却有可能会早醒、迟醒或者无法进入到能具有精力回复性质的更深睡眠当中。

So even if we do manage to fall asleep, chances are we'll wake later, wake early, or not be able to reach the deeper levels of restorative sleep we need.

youdao