If you step back from the day-to-day fuss over individual opinion polls and ignore all the loose talk about Green “surges” and Tory “crossovers”, not much has really changed over the past few weeks.

January’s poll averages did not represent that great a departure from those of the previous month.

The Tories added 0.5 points, but this still put them on only 32.1%: 0.2 points lower than where they were in January 2014.

Ukip fell 0.4 points, but their rating of 15.1% is still the third highest they have ever scored.

The Lib Dems hit yet another record low: 7.5%, down 0.1 points on December. A year ago, they were nudging 10%. The party has shed a quarter of its poll support in 12 months.

As for Labour, its poll average is now the lowest since 2010. 33.0% represents a fall of 0.4 points on December. A year ago the party was on 38%.

The Tories’ average of 32.1% is 0.4 points up on where they were two years ago. By that measure, it would take the party 24 years to get its poll average back to the level it was at the 2010 general election.

By contrast, if the party was to repeat its performance in January 2015 and go on adding 0.5 points every month, it will be at 34.1% by the time of the general election in May, and would hit its 2010 level (36.9%) by November.

If Labour’s slide continues at the same monthly rate, the party will be down at 31.4% by May.

These kinds of vote shares would still likely mean a hung parliament, of course, and almost certainly one where the Tories were down on the number of seats they won in 2010.

But that’s as far we can go in extrapolating election results from poll trends. As I said recently, it’s vital to remember that the polls won’t tell us anything precise about the result. They tell their own story, and very interesting it is too, but it’s not one from which we should make any assumptions about what will happen on 7 May. Polls are nationwide snapshots. The general election is not a nationwide contest.