The title was contested over an eight round series with one race per round.

The championship was contested over a three round series with two races per round.

The championship was contested over a six round series with one race per round.

The title was contested over a five round series.

The title was contested over an eight round series with three races per round.

The championship was contested over a seven round series with each round held as a single race.

The title was contested over a three round series with one race per round.

The title was contested over a six round series with two races per round.

The title was contested over an eight round series.

The championship was contested over an eight round series which ran from 9 April to 29 October 1989.