PHOENIX—Goldman Sachs expects the U.S. economy will grow 2.7% in 2011 and 3.6% in 2012.

Heather Shemilt, a managing director and head of the pensions, endowments and foundations group at Goldman Sachs, said that this would represent three years of "respectable" growth .

Shemilt said at Information Management Network’s “Super Bowl of Indexing” Monday that U.S. GDP has increased 2.63% in the first three quarters of this year. She also said that the S&P 500 Index is up 11% this year, and emerging markets have increased 12%. Goldman project the S&P 500 will rise 12% next year and 11% in 2012.

Looking abroad, Goldman projects global GDP growth of 4.5% in 2011 and 4.8% in 2012.

But that does not mean the challenges facing the economy will disappear, Shemilt said.

“2010 has still been a tough year," she said. "Year-to-date the Chicago Board Options Exchange Market Volatility Index is down 11%, but we should not be lulled into complacency. In April the VIX was down 28%. The U.S. dollar has fallen 20% year-to-date, primarily on fears of European debt. Oil is trading at $73 to $93 a barrel. Gold is up 30% to $1,400 an ounce, and could rise 20% or more in 2011. And pension liabilities are unchanged.”

Looking to 2011, the risks continue, Shemilt said, most notably “the contagion of European debt problems, U.S. fiscal and tax policies, and inflation.”