WASHINGTON -- Government efforts to funnel hundreds of billions of dollars into the U.S. economy appear to be helping the U.S. climb out of the worst recession in decades.

But there's little agreement about which programs are having the biggest impact. Some economists argue that efforts such as the Federal Reserve's aggressive buying of Treasury debt and mortgage-backed securities, as well as government efforts to shore up banks, are providing a bigger boost than the administration's $787 billion stimulus package.

The U.S. economy is beginning to show signs of improvement, with many economists asserting the worst is past and data pointing to stronger-than-expected growth. On Tuesday, data showed manufacturing grew in August for the first time in more than a year. "There's a method to the madness. We're getting out of this," said Brian Bethune, chief U.S. financial economist at IHS Global Insight.

Much of the stimulus spending is just beginning to trickle through the economy, with spending expected to peak sometime later this year or in early 2010. The government has funneled about $60 billion of the $288 billion in promised tax cuts to U.S. households, while about $84 billion of the $499 billion in spending has been paid. About $200 billion has been promised to certain projects, such as infrastructure and energy projects.

Economists say the money out the door -- combined with the expectation of additional funds flowing soon -- is fueling growth above where it would have been without any government action.