New Zealand Oil & Gas widened its first-half loss as it wrote down the value of its Tui and Maari investments and switched its accounting policy to cope with a cheaper oil environment.

The Wellington-based company posted a net loss after minorities of $27.6 million, or 7.9c a share, in the six months ended December 31, compared to a loss of $7.7 million, or 1.8c, a year earlier.

The latest loss included an $8.7 million impairment charge on the Tui oil and gas field and a $26.8 million charge on the Maari field after NZ Oil & Gas moved to a "successful efforts" method of accounting, which recognises all general exploration and evaluation costs as expenses as they're incurred, except direct costs of acquiring exploration rights, drilling wells and evaluating results.

Costs of successful exploration are capitalised as assets pending the outcome of a well.


Revenue rose 21 per cent to $65.4 million as Cue Energy Resources made a bigger contribution after being taken over last year, helping offset declines from NZ Oil & Gas' Tui and Kupe investments.

New Zealand Oil & Gas

For the six months to December 31:

• $27.6m loss, up 258 per cent.

• $65.4m revenue, up 21 per cent.

• $31.7m operating cash inflow, up 40 per cent.