Company results due next month look set to belie what business confidence surveys suggested was a slump over the second half of 2019.
Many of the sharemarket's big guns are due to report their interim results covering the six months to December 31.
Among them are a2 Milk and the big four power generator/retailers - Meridian, Contact, Mercury and Genesis.
Fletcher Building, Air NZ, Auckland International Airport, Spark and Chorus will also report over the month.
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As has been the case for several of the last reporting seasons, analysts will be keen to see whether earnings can justify today's very high share prices.
ANZ's Business Outlook surveys painted a grim picture of the economy towards the end of last year, but that did not stop the sharemarket's record breaking run.
"It looks like businesses have gone past that period of negativity," Mark Lister, head of private wealth research at Craigs Investment Partners, said.
"The NZX50 Index put on 30 per cent last year - the strongest year in its history," he said.
"That does not line up with an economy that is starting to falter."
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"It's going to be an important reporting season because share prices have been so strong - and earnings need to justify them," Lister said.
Most of the power generators should be "pretty solid", with not too many surprises, thanks to generally favourable generating conditions.
However Auckland International Airport, Air New Zealand and Tourism Holdings - could feel the brunt of a slowdown in the tourism sector.
Lister said a2 Milk will be the one to watch, particularly in light of last year's disruption to the management team, which saw the controversial chief executive Jayne Hrdlicka depart.
Former chief executive Geoff Babidge has stepped back into the role while new CEO is found.
Investors will be keen to establish whether the management shakeup had any have impact on the company's record breaking earnings performance.
At last year's annual meeting, a2 Milk said it anticipated revenue being in a range of $780m to $800m over the first half.
A result at the top end of the range would represent a 27 per cent improvement over the revenue figure for the same period in 2018.
The company's share price has fully recovered from the weakness that arose from the management shakeup, closing on Friday at $16.01.
A2 Milk is expected to report on February 27.
Stocks with exposure to the flagging Australian economy - Fletcher Building and Sky City Entertainment - may start to feel the pinch as that economy slows, Lister said.
Those with exposure the Australian economy may face some challenges.
Lister pointed to Downer EDI slashing its full-year profits guidance by A$65 million due to cost blowouts on two projects and CIMIC - formerly Leighton Holdings - post-tax impairment of A$1.8 billion as signs of stress in Australian construction.
Investors will also be keen to establish whether the worst is behind Fletcher Building, after a series of disappointing results.
The company said last November that it its core divisions - Building Products, Concrete, and Distribution - remained on track.
Port of Tauranga's first half result is due. The company's first quarter saw cargo volumes slightly less than the prior corresponding quarter.
Refining NZ's result for calendar 2019 is also expected.
The company has already said its full year processing fee income was $242m over the year from $258.7m in 2018.
Its gross refining margin slumped to US$2.62/barrel, down from US$5.34/barrel in 2018.