In fact, the overall accumulation of wealth is being offset by widening income disparity.

Now the richest 20 per cent of people in Hong Kong receive more than 50 per cent of the total income, while the poorest 20 per cent take less than 5 per cent. In 1996, there were about 305,000 households with income below HK$8,000 but in 2010 the number had grown to 485,000.

The meagre earnings of the low-paid means they are much less equipped to cope with economic cycles, which have become shorter but of greater intensity.

So when the minimum wage was introduced last year it was hailed as one of the most significant developments in a city used to thriving on a laissez-faire economy.

The HK$28 minimum hourly wage gave at least 300,000 workers who had been receiving less than that a chance to improve their lives. But the law is by no means a magic wand able to sweep away inequality with one wave.

Lam Wai-kau, 62, who migrated from Taishan in Guangdong six years ago, saw his wages increase HK$1,000 to HK$6,944. Lam, a cleaner with a Housing Department contractor in a public housing estate in Shek Kip Mei, works from 7am to 5pm daily and his two-hour lunch breaks are unpaid.

'I used to work on a farm and I thought that was the hardest life. I didn't know working here would be even more exhausting, and the working hours longer,' he says.

During the lunch break, Lam walks from Shek Kip Mei to his tiny Sham Shui Po home - a 100-square-feet attic that he cannot stand up straight in - and cooks his lunch to save money.

'My son says it's like a jail cell. I hope one day I can get a public rental flat, then I will furnish it properly and my son can come and stay,' Lam says.

Lam's dream of better shelter is a distant one as there are more than 175,000 applicants on the public housing waiting list, 18 per cent more than in 1997.

In a city where housing is the foremost social problem, most people's lives revolve around property and its price, which remains as high as or even higher than in 1997, a peak year for the market. Wealth ballooned for those who owned flats during the property boom, but frustrations also grew for those who could not afford the down payment for a decent flat or whose wage growth never matched the rising flat prices.

The impact of high accommodation costs and shop rents are felt across society. Some people have retreated into subdivided flats with fire or safety hazards, while street-level shops are forced upstairs to stay in business as luxury brands evict them from the core shopping areas.

Even for those who can afford their own home, fluctuations in the property market in the past 15 years have kept them on edge.

Jason Poon Chuk-hung, like many other property owners, felt as though he was riding a rollercoaster. In 1998, when the market was devastated by financial turmoil and over-building, he was struggling to repay the mortgages on his negative-equity properties - a flat in Kowloon Bay's Telford Garden, a double apartment in Metro Harbour View in Tai Kok Tsui and two car-parking spaces.

'I was living like a zombie. It's not that I could not repay the mortgage, but it's the psychological pressure, the feeling that you are working so hard to pay for something that is not actually yours, that hurts,' says Poon, a building engineer who runs his own business.

The Telford Garden flat he bought for HK$2.22 million slumped to a little more than HK$1 million, and the double unit he bought for HK$4.7 million plunged to HK$3 million. Things are looking better now: the double unit is worth HK$12 million.

While it is temping to cash in his gain and move to a nicer apartment in Tsim Sha Tsui, Poon is worried that government intervention might spark another slump. 'As I've grown older, I am less adventurous with investments,' he says.

Income might not be distributed equally and private flats are sometimes a luxury, but there is one thing of which everyone, rich or poor, has more than a fair share: air pollution.

As introduction of cleaner bus engines, LPG-powered taxis and minibuses and an idling-engine ban seem to do little to abate the choking fug, there are reports of expatriates refusing postings to Hong Kong because of the foul air, while others who have spent decades in the city reluctantly pack their bags out of concern for their families' health.

One of the latter is Eric Bohm, chief executive officer of WWF Hong Kong, who came to Hong Kong in 1981 and is now leaving for England.

'One big disappointment over the years is that the government has been unable to address the air quality issue,' Bohm said in a recent interview. 'My wife has asthma and the air quality here is not good. She had pneumonia twice last year, triggered by bad air and irritation. So I say enough is enough.'

According to the Hedley index, which is designed to track the impact of air pollution, there are more than 3,000 premature deaths associated with air pollution each year.

While the past 15 years have seen intensified clean-up efforts in Hong Kong and Guangdong to reduce the level of floating particles and sulphur dioxides across the region generally, progress has fallen far short of people's expectations, in particular by the roadside.

In 1999, the average annual roadside nitrogen dioxide reading was 57 micrograms per cubic metre of air. Last year it had more than doubled to 123 - more than three times the World Health Organisation's recommended level.

Making matters worse, the hot exhaust fumes of old vehicles burning dirty diesel are often trapped in the canyon-like spaces between high rises, leaving the city hotter and dirtier.

The idling-engine ban, introduced after a decade of debate but heavily toned down amid pressure from the transport industry, may make a stroll along a busy street a little less unpleasant.

But other measures deemed more urgent and necessary by many environmentalists, such as replacing all old dirty-diesel vehicles - including thousands of franchised buses - are still awaited.

As well as air quality, the city's overall environmental performance card does not look good.

The terms 'wall buildings' and 'light pollution' were barely heard in 1997 but now are in almost daily use, thanks to a building boom of poorly designed high-rises and misused lighting technology.

Mary Mulvihill, a long time resident of Tsim Sha Tsui, says her quality of life has deteriorated, in particular with the completion of a building - The ONE - next to her home. She says the shopping mall has created a string of environmental nuisances - noise, light pollution and traffic chaos. It has also destroyed a neighbourhood of resident-friendly shops. She filed numerous complaints to the building owner, management, shop operators and government before becoming involved in a legal dispute that left her owing HK$53,000 in legal fees.

'All these things can be avoided if buildings are properly planned and designed. There is no need to inflict punishment on local people,' she says.

While Mulvihill fought to protect her quality of life from being eroded by a single building, many more were struggling to save their homes.

An example was the months-long protest in 2010 by Tsoi Yuen Tsuen residents being displaced by the high-speed cross-border railway that redefined the conflicts between conservation and development.

'The Tsoi Yuen Tsuen movement has inspired me to think about what 'home' is, what a good lifestyle is,' says activist Chan Kim-ching, who helps other similarly threatened villagers. 'You feel attached to the land you live on and you do not want to move every few years.'

3

The factor by which Hong Kong's roadside readings of nitrogen dioxide exceeded the WHO's recommended level last year