Somalia is now more at risk from terrorist attacks than Iraq, Pakistan, Afghanistan and Colombia, according to a global ranking developed by risks advisory firm Maplecroft.

It shows that Somalia moved from 4 to 1 in this year’s Terrorism Risk Index (TRI) and has the highest number of deaths from terrorism per population, surpassing Iraq and Afghanistan in the number of fatalities per terrorist attack.

According to Maplecroft’s analysis, Somalia experienced 556 terrorist incidents, killing a total of 1,437 people and wounding 3,408 between June 2009 and June 2010.

Yemen has also jumped into the extreme risk category for the first time. The country has seen a very significant increase in the number of terrorist incidents on its own soil with a total of 109 attacks between June 2009 and June 2010, Maplecroft reports.

A recent incident in which two parcel bombs sent from the Yemen were discovered aboard cargo planes en route to the U.S. minutes before detonation, highlights the elevated risk given this country by Maplecroft.

The index ranks the U.S. (33) at higher risk for a terrorist attack than France (44) and the United Kingdom (46), though none of the major Western economies fall within the high or extreme risk bracket.

Greece saw the largest jump in rankings from 57 to 24, overtaking Spain (27) to become the European country most at risk from terrorist attacks.

Check out a recent I.I.I. paper for more information on why terrorism risk is likely to remain a serious threat in the decade ahead and I.I.I. facts and stats on terrorism.