The divorce rate of high-salaried women is more than twice the average of all women and soars to four times the national average among women executives earning $50,000 or more, a national women's magazine says. And, of adult women in the $25,000-and-above income bracket, 15 percent, more than twice the average for all women, were divorced at the time the data were gathered, the magazine said. The magazine, Glamour, also said that women who delayed marrying until they were past 30 divorced more than those who married in their 20s, and women who went on to graduate school divorced more often than those who had only four years of college. Glamour based its findings on 1978 Census Bureau data, but it said that a study by the management consulting firm of Heidrick and Struggles turned up similar findings. According to the firm's figures, nearly a third of women officers of major companies earning $50,000 or more were currently divorced -- more than four times the national average. Glamour said it is not clear what causes the high divorce rate: Do men find these women less desirable? Do women with high incomes divorce because they can afford to maintain their own households: Or does a job-salary competition cause friction? Lawyer Jean Bilger, 28, who earned $45,000 a year as a lawyer and this year became a state administrative judge, divorced her first husband, in part because "he demanded so much from me that I couldn't meet those demands and practice law at the same time." On the other hand, the magazine also quoted a sociologist at the Graduate Center of the City University of New York, Cynthia Fuchs Epstein, who found while doing research for a book on women in law, that the majority of women who had become partners in Wall Street firms were married. "The total combination of extreme competence in work, coupled with the fact that they're seen as being in control of their personal lives, adds up to an attractive package," Epstein said. "What stands out in all the soul-searching and debate is how rarely these women entertain the notion of bridling themselves, of deliberately blunting their aspirations," Glamour said. "Work gives them rewards beyond money, and they have invested heavily in it."