You've probably heard it said that married couples often fight about money. New research shows exactly how often that's true. According to a survey conducted by the American Institute of CPAs financial matters trigger an average of three arguments per month for married couples. That rises to four finance-related articles per month for married couples aged 45 to 54. The most common source of contention is disagreement over what's a "want" and what's a "need." The next most common issues are unexpected expenses and insufficient savings.