1. A computer-implemented method to estimate the time to implement a regression test, the method comprising: receiving, at a host computer system, a productivity table indicating a plurality of productivity norms for each type of automation script in a plurality of automation script types at a plurality of complexity levels, each productivity norm indicative of an expected time to implement a corresponding type of automation script at a corresponding complexity level; receiving, at the host computer system, a list of test flows associated with conducting a regression test, each test flow corresponding to at least one type of automation script in the plurality of automation script types; receiving, at the host computer system, a selection of a complexity level for each test flow in the list of test flows, the complexity level selected based upon: the available resources of a computer system on which the regression test will be performed; the environment in which the regression test will be performed; statistical data describing scripts used in the test flow; the types of scripts used in the test flow; test definition documentation; and the technical knowledge of personnel associated with implementing the test flow; determining, with a processor associated with the host computer system, an expected time to implement each test flow in the list of test flows at the complexity level selected for each test flow based upon the productivity table; determining, with a processor associated with the host computer system, a total expected time to implement the regression test based upon the expected implementation time of each test flow in the list of test flows; and storing, in the host computer system, the total expected time to implement the regression test.