The Census Bureau made the announcement on October 17 that the population of the United States crossed the 300 million threshold. The makeup of the population is changing, too. According to the Bureau's American Community Survey, 55.2 million (approximately 49%) of the nation's 111.1 million households in 2005 contained married couples--with or without children. Since 2000, those identifying themselves as unmarried opposite-sex couples increased by about 14%. Although they may choose to live together for different reasons, unmarried partners do share something--different, potentially more complicated financial issues than those faced by married couples.