With its international brands, upmarket cafes, multiplex and fashion outlets, the DLF Select CityWalk mall in south Delhi is a monument to booming India. Opened five years ago, it is still a favourite among the new middle class in the emerging economic giant's teeming capital.

But for Amarinder Singh Chopra, a hotelier shopping for clothes for his newborn baby in Mothercare, the shopping experience is not entirely carefree, whatever relief the air conditioning provides from the 40-degree temperatures outside.

"I won't compromise on quality for my kids so I am coming here, but I'm being a little bit careful," said the 38-year-old, who runs a luxury safari-style hotel 250 miles north of Delhi.

Many others share Chopra's sentiments. For weeks there has been a steady stream of bad news. The headline figures for economic growth in India have been revised downwards; prices continue to rise; government spending continues to grow faster than tax revenues, and the rupee has slumped. In the week beginning 21 May the currency hit an all-time low against the dollar.

The slowdown comes after nearly 20 years of almost unbroken rapid growth, and fears are growing of an end to, or at least a pause in, the long-running boom.

"We've been OK until now, but from now on all the economics will start impacting. People are feeling the crunch. The brakes are coming on," Chopra said.

One commentator raised the prospect of a "lost decade" for India. For some the change is already evident.

Manish Chandra, a 41-year-old Delhi-based retail designer, will not be heading overseas this summer. After trips to Florida, around Italy and across central Asia, this year, he said, he was unwilling to stray too far from his business, concerned by the additional expense caused by the plunging rupee.

"We are feeling the pinch. My perception is that the next year or two are going to be shaky," Chandra said.

India has enjoyed decades of steady growth after the humiliating crisis that forced the dismantling of the quasi-socialist planned economy in 1991. Growth rates have stayed between 7% and 9% for much of the last 10 years.

Investment bank Morgan Stanley has just cut its forecast of India's 2012 economic growth to 6.3%, from nearly 7%, and reduced the forecast for 2013 to 6.8% from 7.5%.

Analysts cite a range of factors for the slowdown. Some are external, such as the falling demand for exports and withdrawal of hundreds of millions of dollars of capital by western funds seeking safer havens during a global crisis. But many others factors are internal.

Self-inflicted

"A lot of the pain is self-inflicted," said Shubhada Rao, chief analyst with the local Yes Bank. The problems include chronic gaps in infrastructure, a shortage of skilled labour, unproductive farming, huge government expenditure on inefficient subsidies, and barriers to overseas companies looking to invest.

Then there is the entrenched corruption at all levels, a proposal for punitive retrospective taxation on foreign companies and, perhaps more than anything, the failure of a weak, divided administration to pass the reforms that most experts say are necessary.

Rao said that though the Indian economy was not yet "in intensive care", the symptoms were building up.

It is the country's newly affluent middle classes who are likely to find any downturn more of a shock, if just because their expectations are so much higher. Over recent years rich individuals have seen their wealth grow massively, while hundreds of millions more have watched their income steadily rise. The bottom third, however, has experienced a much lower rate of increase – perhaps only 2%.

According to Rao, growth of 7%-8% each year is the minimum necessary to "lower inequality and improve quality of life for everybody". Few predict a return to those levels for several years.

One question is whether the belt-tightening among the affluent will feed through into political discontent. Graft has become a big issue in recent years, with a series of demonstrations last year forcing the incumbent Congress party on to the defensive.



Corruption

Only 22% of respondents in a recent poll said their standard of living had risen in the last three years since the government acquired power.

One repeated call has been for a crackdown on "black money". Some estimate that more than two-thirds of the Indian economy is unofficial.

One sector where black money plays a massive role is real estate. Anckur Srivasttava, a property market analyst in the booming Delhi satellite town of Gurgaon, said that the sheer quantity of undeclared wealth in the sector had protected real estate in India from the international downturn.

"Too much has been built too fast, but, in general, real estate is not in a negative phase. Politicians and bureaucrats are generating millions of dollars each month and in somewhere like Gurgaon you can invest that without it even causing a ripple," Srivasttava said.

Owning a flat in Gurgaon, or in a similar satellite town, is one of the most common ambitions for Delhi's upwardly mobile middle class.

Rajji Rai, who has run a travel agency for more than 30 years and enjoyed decades of continuously growing demand, is confident the public will remain unfazed. "Indians are used to all these problems. There is massive tolerance."

But Deepak Malhotra, a Delhi businessman whose outsourcing company runs telesales teams for Indian companies, was less sanguine. "Sentiment is very weak. I don't know how many people are actually making money from their businesses right now," he said.

His teams sell for companies that focus on the aspirations and insecurities of the new middle class, offering "dream homes", insurance, public speaking lessons and job opportunities.

There is still plenty of demand for Malhotra's services but less for such products. "We are getting the contracts, but, every day, selling is getting harder," he said.