The list was created by veteran entertainment journalist James Ulmer, who developed a 100-point method to quantify a star's value to a film production, in terms of getting a film financed and the cameras rolling.
Tom Hanks and Tom Cruise have topped the latest ranking in 2006. Ulmer's latest Top Ten List from 2006 also includes:
James Ulmer calls his method "The Ulmer Scale". The A-list is part of a larger guide called The Hot List that has become an industry-standard guide in Hollywood. Lesser-known actors inhabit the B+, B, and C lists, and there is even a dreaded "Bottom of the Heap."
If an actor has 100 points on the Ulmer Scale for a given budget, a movie on that budgetary level can have 100% of its financing guaranteed, based solely on that actor's participation. Very few stars have such power in the "$25 million or over" range, and the ones nearest to it occupy the A-list. Ulmer has also developed a Hot List of directors.