Experts warn New Zealanders after worldwide sharemarket plunge

Experts are warning New Zealand investors not to panic after the Dow Jones rollercoaster slashed stock values on Tuesday.

Wall Street suffered its biggest ever one day loss with hundreds of billions of dollars wiped from the value of shares around the world.

The New Zealand market was closed on Waitangi Day, and there are fears the plunging prices could spread to New Zealand when the NZX opens at 10am on Wednesday.

But Newsroom Pro editor Bernard Hickey says the market has risen 40 percent since Donald Trump was elected, and Tuesday's five percent drop was to be expected.

He argues this doesn't compare to the Global Financial Crisis (GFC) and there is no need to panic.

"I don't think this is the beginning of the next GFC at all," he says.

"This is the most-predicted correction in the stock market in the history of stock markets."

Mr Hickey says the plunge will affect New Zealanders' KiwiSaver accounts - but this won't matter for most people in the long term.

"Those people who are checking their balances daily will get a bit of a fright but for most people they're looking at 10, 20, 30 years down the track before they actually withdraw their KiwiSaver money," he says.

"Unless you happen to be one of those people taking their money out to put a deposit on a house... you should be relatively relaxed."

US expert John Fenoglio agrees, and urges caution before selling off.

"Most financial experts say 'don't panic', they say it's more important to watch and wait before making any drastic changes to your portfolio," he says.