Singapore moved up two spots to fifth place in the World Economic Forum's 2008 Global Competitiveness Index on Wednesday, as it pulled away from other Asian economies.

It was a different fortune for the next most competitive Asian economy, Japan, which dropped to ninth from its eighth spot last year when Singapore overtook Japan in the annual ranking.

Regulated European and Asian countries topped the survey, as the financial crisis started to take its toll on economies.

Singapore's improvement came on the strength of its institutional environment. It is among the top two countries for the efficiency of all its markets - goods, labour and financial. The republic's world-class infrastructure also played its part, as it leads the world in the quality of its port and air transport facilities.

In the survey, respondents ranked inflation as the most problematic factor of doing business in Singapore. Workforce and tax issues also played a part, with an inadequately educated workforce, restrictive labor regulations, tax rates and tax regulations also cited as being problematic factors.

The city state's ranking was also constrained by its domestic size and mixed performance in the macroeconomic stability pillar. Its interest rate spread was ranked 59th, while government debt was ranked  121st.

The survey was conducted between January and May this year, so the index does not reflect the latest developments in the financial crisis. But Jennifer Blanke, senior economist of the forum, said the index aimed to take a longer-term view, and on that basis the United States' ranking was fully justified.

The United States remained in first place in the index, its flexible labour markets and innovative businesses well positioned to help it out of the global financial crisis.

But Britain, where the financial sector plays a bigger role, dropped out of the top 10 to rank 12th, while relatively regulated economies like Switzerland, Denmark, Sweden, Finland, Germany and Japan all featured in the top 10.

The index is produced each year by the World Economic Forum, which organises the annual Davos meeting of business and political leaders.

This year the index, combining economic data with a survey of business executives, covers 134 economies.

Economies are assessed according to 12 "pillars" of competitiveness, ranging from infrastructure and macroeconomic stability to business sophistication and innovation. These are weighted for each economy to reflect their stage of development.

The aim is to assess the factors that determine productivity rather than simply measure market share, the forum says.

Forum researchers acknowledge that as in any such exercise, the data are not always up to date, and the survey can be subjective. But the index is closely followed by governments and by companies planning foreign investments.

Blanke, justifying issuing the index at a time of financial market turmoil, told a briefing "We are looking at structural factors. We are not looking at the business cycle and we're also not necessarily looking at shocks, as big as they are."

"Just because there's a huge financial crisis doesn't mean that we can forget about how good an educational system is or Silicon Valley or whatever it is that is driving productivity in an economy," she said.

China continued to climb this year, up four places to 30, helped by its large market and strong economic performance, but held back by underdeveloped financial markets, the forum said.

Russia also rose sharply, climbing seven places to 51, its big market and oil-fuelled economic performance outweighing institutional weaknesses.

Brazil also rose sharply. But among other big emerging economies, India slipped two places to rank 50 with economic problems and unequal access to health and education outweighing the size of its markets and its business sophistication.