A simple model of earnings, cash flows and accruals is developed by assuming a random walk sales process, variable and fixed costs, accounts receivable and payable, and inventory and applying the accounting process. The model implies earnings better predicts future operating cash flows than does current operating cash flows and the difference varies with the operating cash cycle. Also, the model is used to predict serial and cross correlations of each firm's series. The implications and predictions are tested on a 1337 firm sample over
The relation between earnings and cash flows
. IntroductionEarnings occupy a central position in accounting. It is accounting's summary measure of a firm's performance. Despite theoretical models that value cash flows, accounting earnings is widely used in share valuation and to measure performance in management and debt contracts.Various explanations have been advanced to explain the prominence of accounting earnings and the reasons for its usage. An example is that earnings reflects cash flow forecasts (e.g., Beaver, 1989, p. 98;and Dechow, 1994) and has a higher correlation with value than current does cash flow (e.g., Watts, 1977;and Dechow, 1994). In this paperwe discuss the use of accounting earnings in contracts, reasons for its prominence and the implications for inclusion of cash flow forecasts in earnings. One prediction that emerges is that earnings' inclusion of those forecasts causes earnings to be a better forecast of (and so a better proxy for) future cash flows than current cash flows. This can help explain why earnings is often used instead of operating cash flows in valuation models and performance measures.Based on the discussion of contracting's implications for earnings calculation, we model operating cash flows and the formal accounting process by which forecasted future operating cash flows are incorporated in earnings. The modeling enables us to generate specific integrated predictions for: i) the relative abilities of earnings and operating cash flows to predict future operating cash flows; and ii) firms' time series properties of operating cash flows, accruals and earnings. We also predict cross-sectional variation in the relative forecast-abilities and correlations. The predictions are tested both in-and out of-sample and are generally consistent with the evidence.Dechow (1994) shows working capital accruals offset negative serial correlation in cash flow changes to produce first differences in earnings that are approximately serially uncorrelated.' She also shows that in offsetting serial correlation accruals increase earnings' association with firm value. One of this paper's contributions is to explain the negative serial correlation in operating cash flow changes in particular and the time series properties of earnings, operating cash flows and accruals in general. A second contribution is to explicitly model how the accounting process offsets the negative correlation in operating cash flow changes to produce earnings changes that are less serially...