About 630 million people in the world would move permanently to another country if they had a chance with the United States the most desirable destination by a long way, a global poll shows.

That though was less than a year ago when more than 700 million wanted to emigrate, a drop of 16%, according to the latest findings from Gallup based on interviews with 401,490 adults in 146 countries between 2008 and 2010. The 146 countries represent more than 93% of the world's adult population.

The desire to move was mostly in the developing world, with the largest drop in sub-Saharan Africa. Residents in this region remain the most likely worldwide to express a desire to migrate permanently, with 33% of adults saying they would like to move, but this is down from 38% in earlier polling.

Desire also fell measurably in Latin America from 23% to 20% and in Southeast Asia from 12% to 9%. Yet, in other places around the world, desire remained relatively buoyant. Among European Union residents, for example, the percentage of adults who would like to move to another country permanently remained flat at 20%. The 10% of adults in Northern America who would like to migrate also remained unchanged.

Eighteen countries continue to attract more than 70% of the potential migrants worldwide. The United States continues to be the top desired destination for adults who would like to migrate. About 23% of potential migrants, some 145 million adults worldwide, name the US as their desired future residence followed by 7% naming the UK, then Canada, France, Spain, and Australia which together appeal to at least 25 million adults.

Northern America, which includes the U.S. and Canada, and countries in the European Union continue to be the top draws regionally. Roughly 188 million adults, or about 30% of the total percentage of adults who would like to move worldwide, would like to move to Northern America.

About 178 million adults would like to move to a country in the European Union. However, the EU has the highest percentage of residents worldwide who would like to move there within the region. Out of 178 million who would like to move to an EU country, about 36 million are from within the region.

Gallup's worldwide research indicates that the declining desire to migrate that is evident in some regions could possibly be a by product of the global economic downturn, which could have made the idea of leaving one's own country in uncertain economic times too risky to think about.