"The persistent shortage of workers that has been crimping growth plans at many companies won't be ending anytime soon, according to Manpower Inc.'s latest survey of U.S. employers' hiring plans.</br></br>Demand for employees is still growing, and with unemployment at its current extremely low levels, ""the traditional labor supply is essentially exhausted,"" Manpower said.</br></br>Companies pinched for labor may get a modicum of relief from recent legislative changes that eliminated Social Security earning limits; that freed some older workers from restrictions on their ability to work. But recruiting more workers ""will continue to challenge employers throughout the country,"" Manpower said.</br></br>Of the about 16,000 companies that participated in the survey, about 35% said they expect to be recruiting additional workers in the third quarter.</br></br>That's the highest level seen in the 24 years that the survey has been conducted. During the year-earlier quarter, and again in the second quarter of the current year, the figure was an already very strong 32%."