The U.S. economy added 216,000 jobs in March, bringing unemployment down to a two-year low of 8.8 percent, the Labor Department reported Friday. Almost all the gains came from the private sector, which offset layoffs at local governments. Factories, retailers, education, heath care, and financial services all stepped up hiring. Following a strong February during which 240,000 jobs were added, March marks the first time private hiring surpassed 200,000 for two consecutive months since 2006. Over the last two months, the unemployment rate has fallen a full percentage point, the sharpest drop since 1983.