The strength of the Crown's financial accounts gave the Government the ability to respond to shocks like the cattle disease Mycoplasma bovis, Finance Minister Grant Robertson said yesterday.
The strength of the surplus enabled the Cabinet to stand alongside the dairy industry for the one shot at eradicating the disease.
Treasury figures showed the Government's surplus, revenue, expenses and net debt were tracking in line with forecasts.
Mr Robertson said the surplus for the 10 months ended April was slightly higher than expected.
The operating balance before gains and losses (obegal), the Government's preferred measure of financial strength, was a surplus of $3.4 billon, $159 million higher than forecasts.