Portland has become Maine's economic capital because the city has Maine's largest port, largest population, and is close to Boston (105 miles to the south). Over the years, the local economy has shifted from fishing, manufacturing, and agriculture towards a more service-based economy. Most national financial services organizations such as Bank of America and Key Bank base their Maine operations in Portland. Unum, TruChoice Federal Credit Union, People's United Bank, ImmuCell Corp, and Pioneer Telephone have headquarters here, and Portland's neighboring cities of South Portland, Westbrook and Scarborough, provide homes for other corporations including IDEXX and WEX Inc. Since 1867, Burnham & Morrill Co., maker of B&M Baked Beans, has had its main plant in Portland and is considered a landmark.