New Zealand shares sank as muted earnings guidance from SkyCity Entertainment Group and A2 Milk didn't meet investors' expectations. New Zealand King Salmon shed almost a fifth of its value as warmer water left it with more dead fish.

The S&P/NZX 50 Index dropped 47.41 points, or 0.5 per cent, to 9,966.42. Within the index, 24 stocks fell, 16 rose, and 10 were unchanged. Turnover was $90.9 million.

SkyCity led the benchmark index lower, down 4.9 per cent at $3.88 on a volume of 1.4 million shares, more than twice its 617,000 three-month average. The casino operator lowered its annual guidance on weaker-than-expected trading.

Meanwhile, A2 Milk fell 2.2 per cent to $16.41 on a volume of 1.1 million shares, after reporting a small acceleration in sales growth for the nine months through March.


"Despite the reasonably positive leads from global markets, and good performance in Australian trading, we're off half a percent," said Mark Lister, head of private wealth research at Craigs Investment Partners. "It's not unexpected when you get a few pieces of negative news."

Lister said SkyCity was a little bit softer than predicted, whereas A2 was in line with projections. Investors may have wanted to see something new, given A2 is up 46 per cent so far this year.

Outside the benchmark index, King Salmon sank 18 per cent to $2.45 after warning that warm water had increased its fish mortality rate, meaning its harvest would be smaller than expected for the next two seasons.

"It's another reflection of the risks around some of the agribusinesses, whether it's Comvita or Scales - you can't ignore the risks that are beyond your control," Lister said. Comvita increased 1.9 per cent to $4.24 while Scales was unchanged at $4.98.

Z Energy fell 1.9 per cent to $6.21 ahead of its annual result tomorrow.

Lister doesn't expect the upcoming reporting season to differ much from the February results.

Sky Network Television was the most active stock with 2 million shares changing hands, compared to its 1.2 million 90-day average. It fell 0.8 per cent to $1.21, a record low close. Spark New Zealand traded on just 1.1 million shares, well short of its 5.8 million average, and was unchanged at $3.67.

Ebos Group gained 0.4 per cent at $21.50 when it resumed trading after a halt for a discounted institutional placement. The New Zealand Shareholders' Association criticised the placement for ignoring retail investors and questioned whether an underwrite was needed when it was able to raise more funds than initially sought.


Australia & New Zealand Banking Group posted the biggest gain on the day, up 3.3 per cent at $29.68, although just 29,000 of the dual-listed shares traded locally. ANZ reported a 5 per cent decline in first-half profit, including compensation for bad behaviour identified in the Australian royal commission. Its New Zealand unit reported a 4 per cent decline in local profit.

National Australia Bank and its local subsidiary Bank of New Zealand report tomorrow, and Westpac Banking Corp on Monday. NAB isn't listed in New Zealand, although BNZ has some locally listed bonds. Westpac's dual-listed shares rose 2 per cent to $29.73.

Chorus gained 3.2 per cent to $6.18 on a volume of 344,000 shares, down on its 537,000 average.