Washington, Jan 29 (DPA) The US economy grew at an annual rate of 5.7 percent in the final three months of 2009, according to an initial estimate by the US Commerce Department Friday that marked the biggest quarterly gain in six years.

The fourth-quarter growth rate signals a stronger-than-expected recovery from the deepest US recession in decades and is more than double the 2.2-percent growth of the previous quarter.

Economists had predicted a 4.7-percent gain in a Bloomberg News survey.

The Commerce Department said the rise was due to rising consumer demand, private company inventories and exports. It is the best growth rate since the third quarter of 2003.