Newspoll: trend from 1986 to now
I have played with the historical Newspoll primary vote data to construct a two-party preferred (TPP) vote estimate for the past twenty years. The Newspoll site only has TPP estimates for every poll since late 2002. For the earlier data points, where there was a Newspoll TPP estimate, I have used that estimate; otherwise I have prepared my own mix of herbs and spices to cook one up.
I put the series through a 31-term Henderson moving average filter to identify the underlying trend. The key finding: for almost two years, Rudd’s Labor team has been enjoying an unusually high and sustained level of voter support compared with any government (or opposition) over the past twenty years. Electorally, Rudd (in the first year of his first term) is more popular than Howard or Keating.
The unfiltered series and my usual 13-term Henderson moving average can be found on the polls page.
In case you were wondering, the orange vertical lines mark election dates.