Earnings release dates can predict stock movements If you have good news, you want to rush to tell people about it. If you have bad news, you tend to stall, hoping it will go away or that some good news will come along to dilute it. Companies, it turns out, behave similarly — and therein lies an extraordinary opportunity that most investors have been missing. I recently studied whether the announcements companies make when they reschedule earnings reports contain important information about the firms. This earnings season, for instance, investors may have noticed that Apple Inc.AAPL, +2.06% moved forward its expected earnings announcement date to Oct. 20 from Oct. 28. Meanwhile, Coca-Cola Co. KO, +0.96% has delayed its expected reporting date to Oct. 21 from Oct. 14. What can investors predict from such behavior? Often, quite a lot. When companies shift a scheduled reporting date, the announcement typically appears routine. Some financial reporting dates are set by regulation, but firms have discretion in scheduling earnings reports. In this study, I analyzed the corporate reporting calendars of some 19,000 companies from 2006 through 2013. Wall Street Horizon, Inc., a firm that collects events information of publicly traded companies, provided the data. I discovered that firms which moved up their reporting dates were considerably more likely to report higher earnings, while those that delayed their reporting dates tended to announce earnings declines. The stock values of the companies tracked closely with the earnings trends. For example, on March 3, 2010, Oracle Corp. ORCL, -0.18% issued a press release stating that it expected to announce third-quarter earnings on March 25, 2010. However, in prior years, Oracle had followed a pattern of announcing third-quarter earnings on the third Wednesday of the month and, prior to the press release, the earnings calendar forecasted Oracle's 2010 third-quarter expected earnings announcement date as March 17, 2010 (the third Wednesday of the month). Thus, Oracle in its press release was delaying its earnings report by six trading days. Consistent with the broader findings in my study, Oracle’s earnings report conveyed negative news, in this case a year-over-year quarterly decline in return on assets. Oracle’s stock underperformed the market by roughly two percentage points in the month following the calendar revision.. Indeed, in the month following earnings calendar revisions, shares of firms moving up reporting dates returned 2.6 percentage points more on average than firms that delayed announcements. The excess stock returns were fairly symmetric, with advancers outperforming the market by about 1.3 percentage points, and delayers underperforming by about 1.3 percentage points, in the month immediately following the firms’ reporting date change. Put simply, through their scheduling behavior, companies signal the direction of their earnings. Investors, however, generally fail to react until after the announcements are made. Why do investors miss the signals? The most likely explanation is that the calendar revisions appear routine, lacking salient information about corporate fundamentals. A closer look, though, finds that in their reporting schedules, companies are conveying important, albeit seemingly unintended, information, which could be highly advantageous for an astute investor. By ERIC SO