The Queen will today formally open the final session of this parliament.

We’re already into its fifth year, though this won’t be the fifth session. That’s because the coalition government turned the first session into a marathon sitting that ran from just after the general election in May 2010 right through to May 2012.

The official reason for this change was to align all future state openings with the month of the next general election (May 2015), instead of keeping it in its traditional berth of November or December.

The unofficial reason was to give the coalition a chance to push through its most radical/contentious legislation without fear of bills running out of time and failing to make it into law (as almost happened with the NHS shake-up in England).

All of this means we’re about to begin the fourth session of this parliament, not the fifth. But if you’re feeling a distinct lack of excitement or interest at its onset, I don’t blame you. The fifth year of a five-year parliament is one that history suggests will be largely free from constructive debate and law-making, and instead will be mostly occupied with wrangles, hold-ups and dead-ends.

We’ve had four examples of five-year parliaments in the last 50 years.

Three have ended with the House of Commons’ reputation at a very low ebb, matters of internal party politics taking precedence over the state of the nation, and a sense of all momentum fizzing out well before polling day.

The most recent example was the Labour government of 2005-10. Its final 12 months were dominated by the  MPs’ expenses scandal, including the resignation of the Speaker, plus two failed coups by Labour MPs to replace Gordon Brown as prime minister and the Chilcot inquiry into the Iraq war. Hardly any major legislation was passed, save the 2010 Equality Act.

The one before that was the Conservative government of 1992-97. Its last 12 months were similarly barren in terms of legislation, being most notable for the row over MPs voting themselves a 26% pay increase, the split in the Tory party over Europe, the divorce of the Prince of Wales and Princess Diana, and the complete erosion of the government’s majority, leaving John Major prime minister of a minority administration relying wholly on Ulster Unionist MPs for survival. It was the longest peacetime parliament since the Quinquennial Act of 1911 reduced the maximum possible length of British parliaments from seven to five years.

A third example was the Labour government of 1974-79. This didn’t run quite the full five years, ending six months before an election would have to take place. But it too petered out against a backdrop of a government having lost its working majority and inter-party squabbling over parliamentary procedures, this time over the collapse of a Labour-Liberal pact as well as devolution referendums in Scotland and Wales. The election was triggered when the government was defeated on a vote of confidence.

Note that each of these three five-year parliaments ended with the government going on to lose the subsequent general election.

The fourth example from the past 50 years bucks this trend. The Conservative government of 1987-92 concluded with an election won by the same party, though with a majority reduced from 102 to 21. Historians love to ponder what may have occurred had Margaret Thatcher not been replaced as prime minister at the end of 1990 with John Major. All we have to go on are the facts, however, and they suggest that a new face in 10 Downing Street, plus victory in the Gulf War in 1991 and the scrapping of the unpopular poll tax, gave the end of this parliament a dynamism and freshness others lacked.

Continuing further back in history, we come next to the Conservative government of 1959-64, the last 12 months of which kicked off with a contest to replace the sitting prime minister Harold Macmillan. The unlikely victor, Sir Alec Douglas-Home, presided over a year of Tory rebellions and by-election losses, a resurgent Labour party under its new leader Harold Wilson, a stalling economy and several nationwide strikes. Sick of election fever, Home announced in the spring of 1964 that polling day would not be for another six months: a tactic that may have made sense on paper, but which merely sent an already weary nation into near-total torpor.

Again, this five-year parliament was followed by the opposition winning the general election.

There are two more examples from the last 100 years: the Labour government of 1945-50, and the Tory government of 1924-29.

The latter conformed to the pattern of the sitting government losing the subsequent election. Stanley Baldwin’s Tory government, struggling with rising unemployment and the legacy of the 1926 general strike, was replaced with a Labour minority administration.

Labour’s 1945-50 government projected a similar air of fatigue towards the end of its days, but the party managed to win the next general election, albeit with a majority reduced from a massive 146 seats to just five. It limped on for a further 20 months before calling another election, which it promptly lost to the Tories.

In short, of the seven five-year parliaments Britain has endured during the past 100 years, five ended in election defeat for the government, while the other two saw landslide majorities reduced to a precarious size.

All but one (1987-92) ended with very little dignity, and to an assorted chorus of mud-slinging, resignations, dithering and emasculation.

Are you looking forward to the next 11 months?