Retirees want their assets to grow rather than being spent, according to a released Tuesday.

Half of retirees expect their assets to grow over the next decade and another 30 percent expect them to remain at the current level, according to the study by Greenwald and Associates, a market research firm, and CANNEX, a data provider for the financial services industry.

Half of those surveyed spend $3,500 a month from guaranteed lifetime income sources, such as Social Security, pensions and annuities. Forty-one percent do not spend any money from their non-guaranteed assets. The survey included 1,002 consumers age 55 to 75 with at least $100,000 in investable assets.

“Our findings demonstrate that most retirees reject the ‘life cycle theory’ generally favored by economists and endorsed by many financial planners that says when people retire they want to systematically spend down their assets. We found that most retirees feel it’s important to preserve their asset levels if they can, and many cut spending to do it,” says Mathew Greenwald, president and CEO of Greenwald & Associates.

Annuities can provide one of those guaranteed income sources, but only 15 percent know that annual payments from annuities are higher than payments from the highest rated bonds, says the study. Only 32 percent know that annuities can cost less for those who purchase them later in life. More women like the idea of an annuity (70 percent) than men (57 percent), possibly because they live longer, according to the study.