agencies, and computer services firms. Jobs in the borough have traditionally been concentrated in manufacturing, but since 1975, Brooklyn has shifted from a manufacturing-based to a service-based economy. In 2004, 215,000 Brooklyn residents worked in the services sector, while 27,500 worked in manufacturing. Although manufacturing has declined, a substantial base has remained in apparel and niche manufacturing concerns such as furniture, fabricated metals, and food products. The pharmaceutical company Pfizer was founded in Brooklyn in 1869 and had a manufacturing plant in the borough for many years that employed thousands of workers, but the plant shut down in 2008. However, new light-manufacturing concerns packaging organic and high-end food have sprung up in the old plant. First established as a shipbuilding facility in 1801, the Brooklyn Navy Yard employed 70,000 people at its peak during World War II and was then the largest employer in the borough. The Missouri, the ship on which the Japanese formally surrendered, was built there, as was the Maine, whose sinking off Havana led to the start of the Spanish–American War. The iron-sided Civil War vessel the Monitor was built in Greenpoint. From 1968 to 1979 Seatrain Shipbuilding was the major employer. Later tenants include industrial design firms, food processing businesses, artisans, and the film and television production industry. About 230 private-sector firms providing 4,000 jobs are at the Yard. Construction and services are the fastest growing sectors. Most employers in Brooklyn are small businesses. In 2000, 91% of the approximately 38,704 business establishments in Brooklyn had fewer than 20 employees. , the borough's unemployment rate was 5.9%. Brooklyn is also home to many banks and credit unions. According to the Federal Deposit Insurance Corporation, there were 37 banks and 26 credit unions operating in the borough in 2010. The rezoning of Downtown Brooklyn has generated over US$10 billion of private investment and $300 million in public improvements since 2004. Brooklyn is also attracting numerous high technology start-up companies, as Silicon Alley, the metonym for New York City's entrepreneurship ecosystem, has expanded from Lower Manhattan into Brooklyn. Parks and other attractions Brooklyn Botanic Garden: adjacent to Prospect Park is the botanical garden, which includes a cherry tree esplanade, a one-acre (0.4 ha) rose garden, a Japanese hill, and pond garden, a fragrance garden, a water lily pond esplanade, several conservatories, a rock garden, a native flora garden, a bonsai tree collection, and children's gardens and discovery