It also appears that money doesn’t buy marital happiness.
For men with money, infidelity is just another perk. Among men making more than $300,000 a year, 32 percent report cheating, compared to 21 percent of men making less than $35,000 a year. Wealth isn't much of a factor in women's cheating.
"Wealthy men may simply have more dating opportunities than men with less income," says David Frederick, a psychologist at the University of California, Los Angeles, who helped analyze the survey findings.
I like variety
What drives people to cheat? Boredom? The thrill of the forbidden?
Many thrive on the excitement they get from a fling (30 percent overall), but men and women are generally prowling for different things. Men want more sex (44 percent), more satisfying sex (38 percent) and variety (40 percent), findings that closely resemble the 2006 MSNBC.com/Elle magazine survey on monogamy.
"Mostly I’ve cheated because of the excitement," writes a 38-year-old man who took the survey. "I like variety and a more wild sex life than I’ve been able to enjoy with relationship partners."
Women's motives range from the need for more emotional attention (40 percent) to being reassured of their desirability (33 percent) or falling in love with someone else (20 percent).
While women tend to cheat once, guys of all ages are twice as likely to be serial offenders.
"Men are more likely to look for sexual novelty. They might be looking for a sexual outlet without the expectation of continuity," says Sandra Leiblum, director of the Center for Sexual and Relational Health at the Robert Wood Johnson Medical School in Piscataway, N.J., who was not involved in the survey. "And once you satisfy the itch, it recurs."