The state government's improved budget position has been welcomed but the public sector union is fed up with its members doing the heavy lifting.

An audit of the state's 2017-18 finances released on Wednesday showed expense growth of 1.9 per cent, the lowest since 1994-95.

Treasurer Ben Wyatt announced improvement in the state's finances on Wednesday. Credit:AAP

General government revenue grew by nine per cent relative to 2016-17 but the state said this had been largely driven by one-off impacts and underlying revenue growth for 2017-18 was 3.2 per cent.

The forecast $1.3 billion deficit in the 2018-19 budget has been revised down to $618 million and the audit showed the state remained on track to deliver a surplus from 2020-21.