The GEM (Global Entrepreneurship Monitor) has a new paper of Entrepreneurial Activity in 2004 on a global scale. You can download it here (pdf).

- GEM research estimates that 73 million adults are either starting a new business or managing a young business of which they are also an owner.
- Worldwide TEA (Total Entrepreneurial Activity) varies between 1.5 percent and 40 percent worldwide
- Young people tend to be more involved in entrepreneurial activity in every country regardless of the level of GDP per capita.

- The highest TEA can be found in countires (only considering countries where at least three years studies have been conducted) can be found in Uganda, New Zealand, Brazil, Australia



Also there seems to be a stuck in the middle effect though:

"Specifically, for the group of countries participating in GEM 2004, the TEA rate is lowest for countries with per capita GDP of about US $28,000."

Also the GEM report makes clear why entrepreneurial activity is imperative to a economic healthy country:

"Exactly how much influence entrepreneurial activity has on national economic growth is a matter of ongoing debate among economists. Nevertheless, most now agree that entrepreneurship is responsible
for much of the competition and innovation in the business world. This is achieved through the process known as "creative destruction": The innovations introduced by entrepreneurs challenge and render obsolete the technologies and products of existing industries.