From the 1990s onwards, track and field became increasingly more professional and international, as the IAAF gained over two hundred member nations. The IAAF World Championships in Athletics became a fully professional competition with the introduction of prize money in 1997, and in 1998 the IAAF Golden League—an annual series of major track and field meetings in Europe—provided a higher level of economic incentive in the form of a US$1 million jackpot. In 2010, the series was replaced by the more lucrative IAAF Diamond League, a fourteen-meeting series held in Europe, Asia, North America and the Middle East—the first ever worldwide annual series of track and field meetings.