Despite being a relatively overlooked part of the economy, the middle market continues to drive job growth in the U.S.

According to a recent Deloitte survey, 40 percent of middle market companies will add to their workforce this year. That is up from 30 percent last year. And Bureau of Labor statistics show that between March 2011 and March 2012, the middle market generated 1.8 million jobs, more than any other category.

The latest Middle Market Indicator, a survey of nearly 200,000 companies, also shows the resilience of the middle market. Since the recession, mid-market companies have added more than two million jobs, while larger businesses have lost over three million.

The study by Deloitte can be found here.