Accounting software firm falls 3.9 per cent to a 4-month low ahead of today's opening of local earnings season.

New Zealand shares declined amid continued global concerns about economic growth and demand for commodities. Xero, Spark New Zealand and A2 Milk Co fell, while Warehouse Group gained.

The S&P/NZX 50 Index dropped 51.82 points, or 0.9 per cent, to 6,019.49. Within the index, 30 stocks fell, 16 rose and four were unchanged. Turnover was $172 million.

US equities continued to fall overnight yesterday as oil moved lower and European banks extended their slide. Local news was light on the eve of earnings season which begins today with SkyCity Entertainment Group's annual earnings report.

Xero led the index lower, dropping 3.9 per cent to $14.51, a four-and-a-half month low, while fellow tech stock Orion Health Group fell 2.1 per cent to $2.79.


"Stocks like Orion and Xero have US interests, and a core part of their valuation is their ability to grow into the future in offshore markets, and the valuation offshore markets put on stocks like that has been coming back," said Nick Dravitzki, equity analyst at Devon Funds Management.

"The Nasdaq's back significantly in the past couple of weeks, and that's reflected in these prices."

Spark New Zealand fell 3.8 per cent to $3.26. The telecommunications retailer has gained 2.7 per cent this year, outpacing the NZX 50 Index which has fallen 4 per cent.

"There's concerns out there, and in that kind of environment you get material selling. A lot of offshore investors have been selling broadly, just taking risk away," Dravitzki said.

Dual-listed A2 Milk Co dropped 3.8 per cent to $1.77, with Westpac Banking Corp down 2.3 per cent to $30.23 and Australia & New Zealand Banking Group shedding 1.8 per cent to $24.

Heartland Bank fell 3.5 per cent to $1.11, Z Energy lost 2.7 per cent to $6.18, and Metro Performance Glass dropped 2.5 per cent to $1.57. Meridian Energy shed 2.1 per cent to $2.30.

The top performer yesterday was Warehouse Group, up 1.5 per cent to $2.70. Vector rose 1.3 per cent to $3.20, and Auckland International Airport advanced 1.3 per cent to $5.65.

SkyCity Entertainment Group rose 0.9 per cent to $4.44, while Vital Healthcare Property Trust grew 0.8 per cent to $1.89.


Outside the benchmark index, Wynyard Group fell 1.4 per cent to $1.38 - a three-month low.

The company, whose shareholders will vote next week on giving the board more freedom to issue shares, has signed a $2.8 million deal to provide its intelligence software services to a state policing agency.

The three-year contract is Wynyard's first in the country.