The U.S. population is growing at its slowest pace in more than 80 years. New figures from the Census Bureau show the country's population rose by six-tenths of a percent to just over 327 million for the year that ended July 1st. According to the data, the South and West experienced the most growth. The Northeast and Midwest grew at a slower rate. The 2020 census will determine which states will gain or lose congressional seats.