By Steve Goldstein
WASHINGTON (MarketWatch) -- The Philadelphia Fed's manufacturing index stayed in negative territory in August, coming in at negative 7.1 vs. negative 12.9 in July, which marks the fourth consecutive negative reading. Economists polled by MarketWatch expected a negative 5.0 reading. The index is a diffusion one, which means it subtracts the percentage of people reporting a drop in activity from those who report an increase.