TRANSYT-7F is one of the most powerfull computer programs fir traffic signal timing and traffic flow analysis. This paper describes some of the significant improvements over earlier versions of the program package. It is : 1)the implementation of a progression based optimization model that uses the forward progression opportunities (PRDS) concept; 2)improved handling of overlap phases; 3)improved split optimization routine; 4)the calculation of stops was modified to deal more accurately with stops at degrees of saturation near or more than 100%.
