Percentage of Wives Confess Affair?

After all the news about athletes and their affairs, we were wondering what percentage of wives confess to having an affair?

According to an in-depth poll by MSNBC and iVillage, 15 percent of wives willingly confess when they have an affair. Only 7 percent of men who strayed told their wives without being asked. Fifty-five percent of men either not told their wives or lied after being confronted with hard evidence.