Ed Balls has attacked what he calls the "dismal record of failure" of the coalition government because ordinary Britons will be worse off at the upcoming election than they were at the previous one for the first time in almost a century.
Labour said its analysis of data from the House of Commons Library shows working people will have seen the biggest fall in average earnings after inflation of any parliament since the late nineteen century.
And it will be the first parliament since the 1920s in which real earnings have been lower at the end than at the beginning, despite the strengthening UK economic recovery which will be the fastest of any developed Western economy in 2014.
These findings will be unveiled by Balls, Labour's shadow chancellor, in a speech in the marginal constituency of Bedford.
He will also highlight Labour policies to tackle what it dubs the "cost of living crisis", including a hike in the minimum wage, a new lower 10p tax rate, a tax break for firms that pay the living wage, and the expansion of free childcare.
"While David Cameron and George Osborne complacently claim the economy is now fixed, the truth is most people are worse off under the Tories," Balls will say.
"From a Conservative-led government that promised to make working people better off back in 2010, this is a dismal record of failure."
The UK economy is set to grow by around 3% in 2014 and there are signs that the recovery is broadening across all major sectors, having previously relied heavily on household consumption and a healing housing market. And the employment rate is at a record high, while unemployment continues to fall.
But despite the recovery and robust labour market data, productivity is weak and wages are still in real terms in decline. According to the Office for National Statistics (ONS), wages are growing at an annual rate of 0.7% on average against price inflation of 1.9%, with household bills soaring.
The coalition government insists it is doing all it can to balance public finances and underpin household incomes. It inherited a deficit at the Treasury equivalent to 11% of GDP and has embarked on a tough programme of cuts, such as to the welfare bill and local government grants, to erase this.
The National Minimum Wage will rise by 3% to £6.50 an hour in October 2014. And the personal allowance threshold – the amount of earnings an individual can pocket without paying income tax – has already risen to £10,000. The government has also promised to shift the burden of green levies away from energy firms and onto general taxation in order to bring down household energy bills.
However, public sector workers have seen a real terms cut to their pay with salary increases capped at 1% a year. And most benefits have also been restricted to a 1% cap on their annual rises.
There is a general election in 2015.