The US economy grew at a sizzling 5 percent annual rate in the July-September period, the fastest in more than a decade, boosted by strength in consumer spending and business investment.

The Commerce Department on Tuesday sharply revised up its estimate of third-quarter growth from a previous figure of 3.9 percent. Much of the strength came from consumer spending on health care and business spending on structures and computer software.

It was the fastest quarterly growth since the summer of 2003. It followed a 4.6 percent annual growth rate in the April-June quarter.

Most economists think growth is slowing to an annual rate of around 2.5 percent in the current October-December quarter. They foresee growth around 3 percent in 2015.

That would be the strongest figure since the economy expanded 3.3 percent in 2005, two years before the Great Recession began.

The 2007-2009 downturn, the worst since the 1930s, cost millions of people their jobs. Since then, the economy has struggled to regain full health. Even after the recession ended in June 2009, the economy has turned in mediocre growth rates averaging 2.2 percent annually.

But many analysts think growth is finally set to accelerate as more businesses have grown confident about hiring. The country is on track to have its healthiest year for job growth since 1999. In November, employers added 321,000 jobs, the biggest one-month increase in three years.

With more people working and having money to spend, solid gains are expected in consumer spending, which accounts for about 70 percent of the economy.