New Zealand shares fell, led lower by Freightways and Kathmandu Holdings in the last full day of trading before Christmas, while Comvita, Synlait Milk and Moa Group gained.

The S&P/NZX50 Index decreased 19.12 points, or 0.2 per cent, to 8,364.44. Within the index, 27 stocks fell, 15 rose and eight were unchanged. Turnover was $100 million.

"The market's a bit subdued actually, Asia's travelling weaker and we're part of that group, though it's Christmas trading with light volume," said Peter McIntyre, investment adviser at Craigs Investment Partners. "The US tax bill was the main news most markets have been looking at."

The Republican-controlled US House of Representatives gave final approval on Wednesday to the biggest overhaul of the US tax code in 30 years that includes tax cuts and a new deduction on business income.


Tourism Holdings dipped 0.4 per cent to $5.50. The company said the new US corporate tax rate is effective from January 1, but it isn't clear yet whether there is an impact on its tax expense in the current financial year ended June 30 2018.

However, the positive annual recurring financial impact of the tax change on its reported net profit, based on current levels of earnings and current exchange rates, is expected to be between $2.3m and $3m.

"They also have 100 per cent deductibility for capital asset purchases, and being a rental van operator they do have significant capital assets," McIntyre said.

"They're a stock that has run hard and has been typically rated throughout the year by analysts and brokers."

Freightways led the index lower, falling 2.6 per cent to $7.60, with Kathmandu Holdings down 2.1 per cent to $2.37 and Heartland Bank dropping 1.4 per cent to $2.05.

Contact Energy fell 0.4 per cent to $5.57. It signed an agreement to sell its Ahuroa Gas Storage facility in Taranaki to Gas Services New Zealand, which is affiliated with Maui pipeline owner First Gas, for $200m, which it will use to repay debt.

Wellington-based Contact expects to reap net proceeds of $151m from the transaction, reporting a $15m gain on the sale, which will go to repaying debt, it said in a statement.

A $48m tax bill will create extra imputation credits that could allow full imputation for the electricity generator-retailer's targeted 32 cents per share dividend in 2018.


"Part of that transaction means they'll still be able to store gas at the facility," McIntyre said.

"It's a win-win. It means that the net transaction proceeds can be applied to the reduction of debt, but it also means next year's dividend will be fully imputed, which is important for NZ investors. They say that facility was excess to demand, but they're able to access it as well."

Comvita was the best performer, up 2.6 per cent to $8.45, and Synlait Milk rose 2.4 per cent to $7.17.

Sky Network Television gained 1.8 per cent to $2.80.

"It continues to have a raft of substantial shareholder notices through, but it continues to rise and it's been a good performer in the month, up 12.45 per cent," McIntyre said.

"That's probably on the value part of the equation, there's the relationship with Vodafone and it's a good cash flow business - it's not all bad there. It's also a value play, our market is quite expensive."

Outside the benchmark index, Moa Group gained 5.8 per cent to 55 cents. The company said it has nothing to disclose following an NZX price enquiry, which concerned its share price rising from 42 cents on Tuesday to 50 cents on Wednesday, or 19 per cent.

"Week rolling they're up 37.5 per cent but on relatively light volumes," McIntyre said.

"Most investors or analysts are screening for value, and maybe Moa fits into that category as a value play. We've seen Trilogy taken out, maybe some parts of the market see Moa as a potential takeout as well."

Trilogy International, which shares the Business Bakery as a cornerstone investor, was unchanged at $2.81. The skincare and scented candle maker is under a takeover offer from China's Citic Capital Partners for $2.90 a share, or $211m.