Keeping Track: productivity

Worker productivity, a key indicator of long-term economic vitality, rose 8.6 percent in the first quarter – the best performance in nearly 19 years, according to the US Department of Labor.

The index, which measures changes in worker output per hour, means firms are squeezing more from their employees. Still, gains in productivity allow firms to pay workers more without raising prices and let the economy grow without sparking inflation. Analysts say the Fed won't likely raise interest rates until firms start hiring again.