Currently running at around 20% according to this report.
Despite Gordon Brown's pledge to support "hard working families", those who marry or set up home together and establish a stable family are up to 20 per cent poorer, the Civitas study shows.
Actually, if I remember correctly, it was the Tories who started the downgrading of marriage by abolishing various tax reliefs and advantages associated with being married back in the eighties - all Brown has done is continue the progressive liberal policy of destroying the institution of marriage that the Conservatives began.
I'm a firm believer in marriage and I simply can not understand why successive governments have sought to undermine it. It clearly isn't about creating an "equality" as there is a clear disadvantage to being married now - but even if it was about equality, why would you want to make other relationships "equal" to marriage?
It's no secret that the best environment in which to bring up children is in the traditional married family unit - this has been known for so long that every civilisation worthy of the name that has existed had an institution of marriage to support the rearing of children. Only the most stupid or most incredibly arrogant of people would believe that they knew better than the collective knowledge of human civilisations stretching back thousands of years.
Of course, progressives are the most incredibly arrogant people. They really do believe that they know better than anyone either now or in the past. They tear down traditions and institutions and put their own ideas in their place - and when those ideas fail miserably they don't retract and go back to what worked - they work ever more furiously to force ever more destructive changes on us.
The Tories are suggesting that they will bring in tax breaks for married couples - but we all know they don't mean it. What we really need is a conservative party that will say quite simply that the progressive ways do not work and we will go back to those proven methods.
Make no mistake about it - the progressives have torn down every worthwhile institution and tradition we had over the last 50 years. The only way to counter it is to do the same to them. We need a political party with the strength and guts to say "progressivism doesn't work" and the plan to destroy it.
If that party was really the Tory party then they'd be unequivocal about their support for marriage. They would say that marriage is the ONLY relationship that the state should encourage and that they would actively seek to discriminate in favour of marriage - but they don't.
They daren't - because like the Labour Party and the Liberal Democrats the Tory party is a liberal progressive party dedicated to the causes of progressivism and riddled with progressive liberal people, thinkers and policy makers - none more so than their leader.
The really annoying thing is that I know the Tory party membership consists of thousands of people who share the same values as I do, but are so consumed by their loyalty to that party they can not bring themselves to admit that the Conservative party is no longer what they once thought it was.
I know some conservatives will read this and disagree - they'll convince themselves that Cameron is playing a clever game whereby he will win power and then begin a series of typically conservative reforms that will restore our nation, but they are the ones living in a fantasy land, not me.
If anyone can find a single, concrete policy that suggest that is really the case then by all means let me know. You won't, I know, because there aren't any.