WASHINGTON (MarketWatch) - The number of people who applied for unemployment benefits in late March fell to the second lowest amount since the recession ended and touched levels last seen 15 years ago, making initial claims one of the few economic indicators to show underlying strength in a U.S. economy whose growth appears to have slackened in the first quarter. Initial jobless claims fell by 20,000 to a seasonally adjusted 268,000 in the seven days stretching from March 22 to March 28, the government said Thursday. Economists polled by MarketWatch had expected claims to total 285,000. The average of new claims over the past month, meanwhile, declined by 14,750 to 285,500. The four-week average smooths out sharp fluctuations in the more volatile weekly report and is seen as a more accurate predictor of labor-market trends. Historically a level of claims at or below 300,000 is associated with a rapid level of hiring and declining layoffs. Also, the government said continuing claims decreased by 88,000 to a seasonally adjusted 2.33 million in the week ended March 21, marking the lowest level since December 2000. Continuing claims reflect the number of people already receiving benefits. Initial claims from two weeks ago were revised up to 288,000 from 282,000.