Attention, marketers targeting older women: Women age 55 and over are the fastest-growing U.S. demographic group on Facebook in the last three months, according to new data reported by Inside Facebook Monday. The number of women on Facebook is growing faster than men in almost every age group, and women now make up 56.2% of users. Women over 55 have nearly tripled on Facebook since September to more than 717,000, and are nearly double the number of men in the same age group. The Facebook audience overall is getting older as its audience grows well beyond the base of college students it started with. Almost a quarter of U.S. members are now age 35 and over, and 45% are 26 and up. Those ages 18 to 25 make up 43% of users, while teenagers account for 12%. Dove, known for its Real Beauty campaign targeting women over 50, may have been ahead of the curve when it launched its first Facebook application in November.--Mark Walsh