Western Australian politics were initially non-partisan, with individual Members of Parliament choosing to align either with the Government or the Opposition.
Occasional internal splits within the Country Party, now known as the Nationals, are also shown on the chart in differing shades of green.
The table below shows the total number of seats won by the major political parties at each election.
Two features of the Western Australian electoral system are worthy of note in interpreting election results.
[5] This was believed to disproportionately favour the Nationals in terms of parliamentary representation.