By John S. McClenahen Although economic development executives in a few communities across the U.S. report the loss of manufacturing jobs is bottoming out, the overall labor market remains very soft. Indeed, last week initial claims for unemployment insurance rose to 422,000, an increase of 3,000 from the previous week's revised figure of 419,000, the U.S. Labor Department reported on Sept. 11. Economists generally expected a decline in claims to about 400,000. The department's closely watched four-week moving average for initial jobless claims, which smooths out week-to-week variations, also rose in the week ending Sept. 6. The average reached 407,250, some 4,500 higher than the previous week's average of 402,750. It's believed that initial claims for unemployment insurance must move below 400,000 before the U.S. labor market will show improvement.