A year ago, the DJIA stood at 20,172. It peaked last week at 26,616, yielding a 31.95 percent return over that period. It closed on Feb. 5 at 24,345, a yield of 20.69 percent over one year ago. A simple stock pricing model shows that the impact of a corporate tax cut from 35 percent to 21 percent yields a one-time increase in equity values of 21.54 percent. So it could be argued that the market over-reacted to the impact of the tax cut, and that this past week has been no more than a simple correction of that exuberance.