There are a lot of different ways to measure this.
We put out a report recently looking at corporate taxes as a share of revenue. In that report, we make the point that the cuts haven't led to investment. We looked at the machinery, equipment and intellectual property assets as a share of total assets of non-financial corporations. At the same time as taxes were being cut and profit margins were rising, those shares were falling. Corporations are putting that money to all other sorts of uses, most of which don't produce the growth and jobs that they're supposed to.