There are 30 US Post Offices in Somerset County serving a total of 343,156 residents equating to 11,439 residents per post office. It's estimated that approximately 547,715 packages are handled across the 30 county post offices annually. Somerset County is a county located in the U.S. state of New Jersey. As of the 2010 United States Census, the county's population was 323,444, increasing by 25,954 (+8.7%) from the 297,490 counted in the 2000 Census, retaining its position as the state's 13th-most populous county. As of the 2015 Census estimate, the county's population was 333,654, representing a 3.2% increase from 2010. Somerset County is part of the New York Metropolitan Area. Its county seat is Somerville. The most populous place was Franklin Township, with 62,300 residents at the time of the 2010 Census, while Hillsborough Township, covered 55.00 square miles (142.4 km2), the largest total area of any municipality. Somerset County, as of the 2000 Census, was the seventh-wealthiest county in the United States by median household income at $76,933 (third in New Jersey behind Hunterdon County at $79,888 and Morris County at $77,340), fourth in median family income at $90,655 (second in New Jersey behind Hunterdon County at $91,050) and ranked seventh by per capita income at $37,970 (highest in New Jersey). The Bureau of Economic Analysis ranked the county as having the 11th-highest per capita income of all 3,113 counties in the United States (and the highest in New Jersey) as of 2009. In 2012, 49.8 percent of Somerset County residents were college graduates, the highest percentage in the state. Somerset County was created on May 14, 1688, from portions of Middlesex County."