A desirable characteristic of a performance measure is that it be timely, ., measure the effect of the manager's actions on firm value at the time those actions are taken (Holmstrom, 1982). This suggests earnings should incorporate the future cash flow effects of managers' actions. Ifthis was all there were to the determination of earnings, we could understand the robust result from thirty years of evidence that, for shorter horizons, average annual earnings is relatively well-described by a random walk (see Watts and Zimmerman, 1986, chapter 6). 3 Except for discounting, earnings would, like the stock price, capitalize future cash.
