It is troubling not so much because 92 per cent of the sample would equal 43.24 chief executives which would imply that the world's biggest auditor is having difficulty doing its sums.

We can be charitable and attribute the extra bit of a boss to an unfortunate rounding error resulting from cavalier use of percentages.

What is really worrying is the sky-high level of confidence. Short-term optimism is perhaps understandable, considering China's double-digit growth rate last year. But PwC's sample is just as bullish over the longer term with 89 per cent (or 41.83 chief executives) confident their companies' revenues and profits will continue to grow over the next three years. Only one boss said he was 'not confident at all'.

Such high levels of confidence could be construed as a signal that Chinese companies are at the very top of their business cycle and that there is only one way for confidence to go from here: downwards.

The surveyed chief executives' optimism is reflected in the riskiness of their growth strategies. By far the favourite is to expand into new geographical markets, with very nearly half having completed cross-border acquisitions in the past year or expecting to over the next 12 months. Developing new products comes a poor second as a growth strategy, while improving their performance in existing markets trails in third place.

The chief executives' favoured investment destinations also give pause for thought. In Asia, bosses like Vietnam, notorious for its rampant corruption and dubious legal system, Indonesia, where much of the capital is without power and communications following severe flooding, and Thailand, where the military government which seized power last year is busy slapping restrictions on foreign investors.

Chinese company bosses also like South Africa, despite former president F.W. de Klerk's warning last week of 'concerns in Africa about the how and the why a big giant like China is getting involved'.

'We would not like to see this involvement transformed into a new form of colonisation,' Nobel Peace Prize winner Mr de Klerk told a Hong Kong audience last Tuesday, saying that China must not seek to establish 'vassal states' in Africa.

The greatest risks the surveyed bosses perceive to their businesses are scarcities of natural resources, theft of intellectual property and bird flu. Dangers such as political instability, inadequate infrastructure and rising protectionism come a long way down the list. Climate change is the least of their concerns.

If these bosses underestimate the difficulties of expanding abroad, it is also possible they are misjudging the threat of increased competition at home.

'One thing they have not really started to face is actual competition from multinationals coming into China and having a go at grabbing market share,' says Frank Lyn, the head of PwC's China markets practice.

He points to the steady ascent of companies such as Wal-Mart in China's retail market and warns that international giants will begin to muscle into other sectors as well, as they too begin to open up to foreign competition.

That will take time. Given China's current growth rates, it is likely that the bosses' confidence levels for the next 12 months will prove justified. Whether their longer-term optimism will be vindicated is more doubtful. It will be interesting to see if they are still as confident in two or three years time.