The Pensions Ombudsman's (PO) team of legal investigators has been understaffed by a third over the last year due to government restrictions on recruitment.
The organisation was barred from hiring from outside the civil service after the government froze recruitment at Whitehall even though PO staff are not classed as civil servants.
Only two legal investigators now work at the PO, which is unable to hire anyone despite having the budget to do so.
As a result more work will be carried forward to 2011/12 as revealed in the organisation's corporate plan. The plan said 204 cases remain open against a goal of 200.
The PO narrowly missed targets on the time taken to deal with initial inquiries, taking 10.18 weeks to decide what action to take against a goal of 10 weeks.
It beat its target for giving an initial response, taking on average 2.47 days while the goal was three days, according to the report.
The PO's latest IT project is behind schedule and the organisation conceded in its annual report this week that it did not expect to appoint a provider before the current IT contract expired in October.
Ombudsman Tony King said: "Though the year may have been challenging and difficult, we rose to the challenges.
"Overall our productivity exceeded expectations set at the start of the year and our completion times remained much shorter than in years gone by."
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