New Zealand shares rebounded on Wednesday, with the benchmark Top 50 Index gaining 36 points to 5181.
Devon Funds Management portfolio manager Nick Dravitzki said Mainfreight was the star of Wednesday's trading.
"Mainfreight's result was released this morning and it was very strong," Mr Dravitzki said.
"The stock has traded pretty strongly over recent months but this result was even better than the market had expected, and it's traded up strongly on the back of that.
"So that was really driven by revenue being a little bit better than expectations but improving margins driving a higher earnings outcome."
Mainfreight shares rose as high as $14.25 before ending the day at $14, up $1.08, or more than 8 percent.
Tower shares gained 4 cents to $1.74 but Pacific Edge shares fell 8 cents to 89 cents.
The New Zealand dollar finished the day slightly weaker against the currencies of all the country's major trading partners.
Westpac currency strategist Imre Speizer said it was a roller-coaster day for the Kiwi.
"An up and down day for the Kiwi today. The up piece was early this morning, when we received the Fonterra news of its new season's milk payout forecast," Mr Speizer said.
"They said $7. Yes, that's lower than last year. However, the market was thinking it could have been something into low sixes, so this beat those expectations and pushed the Kiwi up as a result.
"Later on in the day ... we had the business confidence survey, and confidence had declined significantly. It's still high but it's taking quite a fall, and the market's reacted to that as well."
In ANZ's latest survey, business optimists continue to swamp pessimists but the overall confidence level plunged 11 points to a net 54 percent.
Just after 5pm, the New Zealand dollar was buying: 85.36 US cents, 92.14 Australian cents, 50.77 pence, 0.6262 euro, 87.01 yen and 5.34 renminbi.