Good news: Infidelity increasing

But detailed analysis of the data from 1991 to 2006, to be presented next month by Dr. Atkins at the Association for Behavioral and Cognitive Therapies conference in Orlando, show some surprising shifts. University of Washington researchers have found that the lifetime rate of infidelity for men over 60 increased to 28 percent in 2006, up from 20 percent in 1991. For women over 60, the increase is more striking: to 15 percent, up from 5 percent in 1991.

The researchers also see big changes in relatively new marriages. About 20 percent of men and 15 percent of women under 35 say they have ever been unfaithful, up from about 15 and 12 percent respectively.