"Bad China data is always going to hurt Aussie more than kiwi," said Imre Speizer, senior market strategist at Westpac Banking Corp in New Zealand, who said a bigger reaction may come during London trading overnight.
"We are within about a cent of parity now," Speizer said. "If we don't see parity tonight, it will be close to it."
The New Zealand dollar touched 99.78 Australian cents last week, its highest level since being allowed to trade freely in 1984.
If the kiwi doesn't break through A$1 tonight, it could reach the milestone should Australian employment data tomorrow print weaker than expected, he said.
Chinese data for March released today showed factory output climbed 5.6 per cent from the same month a year ago, lagging forecasts in a Reuters poll for a 6.9 per cent gain and signalling weaker demand for Australian hard commodity exports.
Chinese retail sales, now watched more closely as China becomes more of a consumer society, expanded 10.2 per cent, missing expectations for a 10.9 per cent gain.
Meanwhile fixed-asset investment advanced 13.5 per cent, lagging behind the 13.8 per cent forecast.
"It's all adding up to more signs of a slowing economy," said Westpac's Speizer.
China's economy is expected to grow 7 percent this year, the lowest in a quarter of a century.