New Zealand shares snapped five days of gains, led lower by Gentrack as investors fretted over how the utilities software developer will cope with ongoing turmoil in Britain's electricity market.

The S&P/NZX 50 Index decreased 14.60 points, or 0.1 per cent, to 11,301.98. Within the index, 26 stocks fell, 22 rose, and two were unchanged. Turnover $108 million.

Gentrack led the market lower, down 6.3 per cent at $3.75, its lowest level since March 2017.

The stock has slumped 27.2 per cent since issuing its third profit warning on November 21, and took another thumping today on news of a major restructuring plan at UK electricity supplier Npower, one of that nation's big six retailers.


"Gentrack has really struggled. We've seen one of the top six energy retailers in discussions around winding up what's called Npower," said Peter McIntyre, an investment adviser at Craigs Investment Partners.

Npower owner E.ON has flagged plans to cut up to 4500 jobs of its 5700 staff in a restructuring plan to hand over millions of customers to E.ON UK, shrinking the big six to the big five.

"With what's happening with energy retailers in the UK, more money's being taken off the table" at Gentrack, he said.

Sky Network Television fell 2.4 per cent to 83 cents after it confirmed it was considering selling its outside broadcasting business.

The pay-TV operator's new chief executive Martin Stewart has singled out online streaming and premium sports as areas for the company to focus on, and adjusted the business to align with that strategy.

Blue-chip stocks Meridian Energy, Kiwi Property Group, Spark New Zealand and Contact Energy were all weaker on volumes of more than a million shares.

Kiwi Property was the most traded stock on a volume of 2.2 million shares, falling 1.6 per cent to $1.555. Meridian declined 1.6 per cent to $4.63, Spark was down 1.3 per cent at $4.48 and Contact Energy decreased 1 per cent to $7.10.

Fletcher Building was also weaker, down 0.8 per cent at $5.19 on a volume of 1.1 million shares, and Infratil dipped 0.2 per cent to $4.89 with 1.2 million shares changing hands.


The NZX50 was one of the few major Asian benchmark indices to decline today, with most of the region buoyed by stronger-than-expected Chinese manufacturing indicators.

Exporter Sanford posted the day's biggest gain, up 2.6 per cent at $7.80 on an unusually small volume of 16,000 shares, compared to its 177,000 average.

Among other export-focused businesses to gain, Pushpay Holdings was up 1.3 per cent at $3.86, A2 Milk rose 1.3 per cent to $15.72, Synlait Milk advanced $1.1 per cent to $9.40, and Fonterra Shareholders' Fund units were up 0.5 per cent at $4.02. Mercury NZ rose 0.5 percent to $4.825 on a volume of 1.6 million shares.

The electricity generator-retailer today said its BBB+ credit rating was affirmed by Standard & Poor's.

Outside the benchmark index, Serko slipped 0.2 per cent to $4.99. The company today received a "please explain" notice from the stock market operator as to why its share price had jumped 17.8 per cent over a four-day period.

Smartpay climbed 11 per cent to 50 cents, recovering some of Friday's decline. The stock has more than doubled since the company last week announced the $70m sale of its New Zealand business to Verifone. Delegat Group was down 2.9 per cent at $11 with just 1757 shares traded, less than its typical 8600 average. The winemaker is scheduled to hold its annual meeting in Auckland tomorrow.