Should the America's Cup be brought back to New Zealand, it would drive more than $500 million into the economy, economists say.
That's if the same number of syndicates and superyachts show up as for the unsuccessful 2003 defence.
That event generated $529 million of value for the New Zealand economy, making a significant contribution to national GDP, an economic impact report commissioned by the Ministry of Tourism found.
And $450 million of that went directly into Auckland.
In the lead up to the 2003 competition, the biggest spenders were the 10 syndicates and their communities, including Team New Zealand, which spent $224 million; superyachts and other yachts ($155 million) and international visitors ($49 million).
And a similar report into the impact of the 1999-2000 America's Cup suggested the regatta generated $640 million of economic activity.
Greg Akehurst, a director of Market Economics, which estimated the 2003 economic impact for the Ministry of Tourism, said he would expect a defence of the Cup to generate $0.5 billion or more in revenue.
However, given that Emirates Team New Zealand hadn't even taken the Cup from Oracle Team USA yet there were many uncertainties.
"It's a $0.5 billion question and a huge unknown," Mr Akehurst said.
"We shouldn't count our chickens before they hatch."
Mr Akehurst spoke to representatives of the marine industry this week and he said their target would be to attract 100 superyachts for the event. On average during the last defence, they spent $1.5 million each.
However, economic conditions had changed in the past decade so it wasn't known whether New Zealand could expect similar numbers of big spenders.
And it's also unknown how many syndicates would challenge for the Cup.
"I think some of the reality is that there just isn't enough talent to build the kind of boats required to be competitive at this level and I think Team New Zealand and Oracle might have gobbled them up and there wasn't anything else ... Oracle even built its boat here."
On Monday, Prime Minister John Key said any defence of the America's Cup in New Zealand was likely to get taxpayer backing from the Government to the tune of more than $40 million.
"I mean I think the Cup would bring the Viaduct bursting back into life once more as it did a decade or so ago."
Meanwhile, Waterfront Auckland has already prepared for an Emirates Team New Zealand win, having earmarked land on six sites for possible syndicate bases.