Quantifying the impact of Hong Kong protests

A demonstrator reads a book as he sits holding an umbrella along with other demonstrators in front of a Chow Tai Fook Jewellery Group Ltd. store during a protest in the Causeway Bay area of Hong Kong, on Saturday, Oct. 4, 2014.
Tomohiro Ohsumi | Bloomberg | Getty Images
A demonstrator reads a book as he sits holding an umbrella along with other demonstrators in front of a Chow Tai Fook Jewellery Group Ltd. store during a protest in the Causeway Bay area of Hong Kong, on Saturday, Oct. 4, 2014.

Hong Kong's pro-democracy protesters have blockaded some of the territory's key shopping areas, and analysts are keeping a running toll on how badly the economy will be hit.

Retail sales were 23.3 percent of Hong Kong's gross domestic product (GDP) in 2013, with spending by non-residents around 14.3 percent of GDP, Deutsche Bank said in a note last week, noting that 75 percent of tourists come from the mainland and these visitors account for 79 percent of tourist spending.

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"This is obvious: the longer these neighborhoods and shopping centers remain obstructed, the greater the economic loss to Hong Kong," it said. "If mainland tourist arrivals drop by one-third for one month, about 0.3 percent of GDP of sales (about 6.8 billion Hong Kong dollars) would be lost. If one-third of all other tourists also stay away for a month, about another 2.3 billion Hong Kong dollars in sales would be lost."

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G2000 founder: Sales fell 35% due to HK protests   

But if the protests don't end soon, more visitors may be discouraged and conferences may be canceled.

"If mainland shoppers and investors feel less welcome, they may reconsider Hong Kong as a shopping destination or as a place to buy property," Deutsche Bank said. But it noted that the impact on property may not be too onerous.

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"Since many Mainland property investors don't actually live in the apartments they buy, it may take a much more serious deterioration in the political atmosphere to deter such investments," it said.

Property sales over the weekend appear to bear that out, with the number of units sold actually rising from the previous weekend amid strong demand from local end-users, according to BNP Paribas, which expects most developers to stick with their launch plans.

CIMB, however, expects property, not tourism, may be the weak link.

"If there is a more prolonged period of protests, then concerns arise when we start to see capital outflows," CIMB said in a note dated Sunday, noting Hong Kong is currently running a current account deficit.Outflows could trigger rising interest rates and risk premiums, further dampening the property sector, it said.

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"If and when property prices start to fall, there will likely be a cascade effect. Property prices falling will lead to more outflows to higher rates to further property prices falls," it said.

But CIMB believes a peaceful outcome is the most likely scenario, with Beijing likely to work to increase economic integration to overcome political differences, rather than seeking to punish the territory.

However, others do expect a longer-term economic hit from the protests.

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"Nothing in Hong Kong benefits from these tantrums," said Ben Collett, head of Asian equities at Sunrise Brokers. "I can't think of one single positive aspect."

He expects tourism plays in Singapore, Korea and Japan may all see a bit of a boost as a result.

Others expect the impact will reverberate beyond the hit to shoppers.

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"The impact of Occupy Central is not confined to tourist spending," Raymond Yeung, senior economist at ANZ, said in a note Friday, citing the potential impact on business and consumer confidence. "If the protests continue to drag on, Hong Kong's fourth quarter outlook will increasingly turn gloomy."

He estimates the protests cost Hong Kong retailers around 2.2 billion Hong Kong dollars, or 6 percent of the month's total retail sales, although he noted the forecast was already cut due to the impact of China's anti-corruption campaign. But he doesn't expect domestic consumption to collapse.

—By CNBC.Com's Leslie Shaffer; Follow her on Twitter @LeslieShaffer1