Every member insurer that prior to April 1, 1993, or after July 27, 1997, shall have paid one or more assessments levied pursuant to RCW
48.32.060(1)(c) shall be entitled to take a credit against any premium tax falling due under RCW
48.14.020. The amount of the credit shall be one-fifth of the aggregate amount of such aggregate assessments paid during such calendar year for each of the five consecutive calendar years beginning with the calendar year following the calendar year in which such assessments are paid. Whenever the allowable credit is or becomes less than one thousand dollars, the entire amount of the credit may be offset against the premium tax at the next time the premium tax is paid.