The "Cullen" superannuation fund has posted a return of 1.66 per cent in November, taking its overall value to $24.93 billion - roughly half the Government's net debt.
Over the last 12 months, as world equity markets soared, it earned 27.76 per cent or about $5.5b. That was more than the Government's asset-sales programme, which is forecast to bring in between $4.6b and $5b.
The fund's annual return since inception in 2003 has been 9.55 per cent.
The latest result comes just a day after new Treasury forecasts saw Finance Minister Bill English bring forward by a year to 2019 the date when he would resume payments to the fund, suspended after National took office.
Labour finance spokesman David Parker said it showed "how feeble the asset-sales programme has been compared to the success of the New Zealand Superannuation Fund".
English had described the fund as "a dog" when it was launched. Stopping contributions had been an "inept" decision, Parker said.
"You can't expect it to deliver those sorts of return every year, but when equities were coming off their lows after the global financial crisis it was the very time they should not have suspended contributions," he said.
Fund size: $24.93 billion
Return since inception: 9.55 per cent per annum.
Return over last 12 months: 27.76 per cent
November return: 1.66 per cent
- The Dominion Post
What do you think of the new banknotes?Related story: Better, brighter Kiwi banknotes