It was discovered that, rather than depending on the monsoon winds, ships could arrive or depart at any time of year by rounding the Philippines. This opened the trade for smaller craft who might only need a few weeks to complete a visit, where the large company vessels still needed 4 to 5 months at minimum. Subsequently, the British and Americans typically always had ships anchored off Pazhou, allowing them to keep their supercargos and staff in the Guangzhou factories all year. During the 1780s, the Spanish also began to send several ships from Manila each year rather than the single vessel they had previously used; they began renting a permanent factory in 1788. (In practice, senior supercargos tended to prefer Macao during the summer regardless and to send their junior officers to deal with off-season trade.)