DRAMATIC one-day declines in stockmarkets don’t often presage broader economic pain (see yesterday’s Daily chart). But what about sustained drops? The gut-wrenching 5.5% fall in the Dow on August 8th might not be cause for concern, but the 14.2% swoon from July 25th to August 8th is a different story. Since 1951, a market decline of 10% or more over 10 days has preceded falling GDP 40% of the time. Three different recessions—1974, 2001 and 2009—are associated with market crashes. Even these bigger, longer falls in equity prices don’t guarantee bad times ahead, though. Markets plunged by 10% or more twice during the late 1990s, yet growth continued to chug along. The biggest ten-day drop of the post-1951 era—a 34.1% dive in 1987—did nothing to derail the American economy. Plunging markets may signal concern about economic conditions, but that concern doesn’t necessarily translate into actual recession.