The expansion into the United States began with the purchase of the Trumbull Shopping Park in Connecticut in 1977, and was followed by three centres in California, Michigan and Connecticut in 1980 and three centres in California, New Jersey and Long Island, New York in 1986. In 1994 Westfield joined with General Growth and Whitehall Real Estate to purchase 19 centres for US$1 billion. Westfield seems to form clusters of centres on particular cities or within a small number of states. They built considerable holdings on the East Coast and in California before expanding into the Midwest. By 2005, the company owned centres in 15 US states.