The latest figures for the £3 billion Work Programme showed more than 168,000 jobseekers have been helped into long-term employment through the programme since it was launched in June 2011.
In the first year of the programme only 24,000 people had found long-term work, but in the past 12 months there has been an additional 144,000, including 37,000 in the past three months.
The Work Programme is aimed at getting people who have been unemployed for more than a year into a job. It is delivered by 18 prime contractors and these providers are paid by results.
Providers involved in the scheme get paid most of their money when someone has stayed in work for six months, or three months for the hardest to help.
The Department for Workplace and Pensions (DWP), which launched the programme, said many more people have started work under it but not yet reached the six-month point.
No benefits
Minister for employment Mark Hoban hailed the scheme as a success and said it is helping people find a job and giving them support to stay in work.
However, the TUC described this as "official spin".
"Just one person in 25 is able to find a proper job after a year on the scheme, and disabled people have seen virtually no benefit since its introduction," said TUC general secretary Frances O'Grady.
"Although there has been an increase in placements for those on the dole, these improvements are starting to tail off.
"The Work Programme is still failing our most vulnerable, and the best way to get to grips with our unemployment crisis would be to offer a jobs guarantee for anyone out of work for at least a year."
The DWP said it has seen a "significant improvement" in Work Programme providers, but admitted that some are still "lagging behind". From August, claimants will be referred to the better performing providers.