The U.S. added more than 2.1 million jobs in 2013 for the third straight year, the best stretch since 2004 to 2006, but more than half of those jobs pay less than $18 an hour, a rate that is just three-quarters of the national average wage, MarketWatch reported. The economy still hasn’t recovered all the jobs lost in the Great Recession, even though the working-age population has grown by about 5 million over the past five years. The U.S. has to add 1.18 million jobs to match its prior peak of 138.1 million, set in the first month of 2008.