WASHINGTON (MarketWatch) – The cost of employing the average U.S. worker rose 0.5% in the second quarter but showed little acceleration despite the tightest labor market in years. Economists surveyed by MarketWatch had expected a 0.6% gain in the employment cost index. Still, there’s little evidence of a broad upswing in the cost of labor. Over the past 12 months, employment costs have risen an unadjusted 2.4%, the government said. That’s just a touch higher than the 2.3% rate one year earlier. The ECI reflects how much companies, governments and nonprofit institutions pay their employees in wages and benefits. Wages – some 70% of employment costs – rose 0.5% in the second quarter. Benefits climbed 0.6%.