Method for reducing backlogged calls is disclosed. According to one embodiment, an initial parameter set providing an initial blocking probability and a timestamp is received. A current time index is determined based on the timestamp. Following, a current blocking probability is calculated based on the initial blocking probability and the current time index. The initial parameter set can also provide a delay period, a throughput rate, an expected new call rate and an initial backlog. The initial blocking probability can be determined, for example, from the throughput rate, expected new call rate and initial backlog. An elapsed time between the timestamp and the current system time is determined, and a current time index is determined by dividing the elapsed time by the delay period. A call request is blocked, for example, when a randomly generated number between 0 and 1 is less than the current blocking probability.