U.S. population growth hit an 80-year low of 0.6% year-over-year in 2018. The slowdown in growth — an already familiar phenomenon in some of the world’s most economically advanced countries — is largely attributable to a declining birthrate.

Slowing population growth is a national phenomenon, however some American cities are bucking broader trend — growing at an annual rate more than triple the comparable U.S. growth rate.

24/7 Wall St. reviewed population change from July 1, 2010 to July 1, 2018 in all U.S. metropolitan areas to identify the fastest growing metro areas in the United States.

While the reasons people move to an area boil down to independent decisions, conditions in many cities on this list offer some more general answers as to why an area might be more attractive than others.

While the aging U.S. population is leading to slowing population growth nationwide, in many of the cities on this list — particularly those in the Sun Belt — inbound migration of retirement-age Americans is largely driving growth. Indeed, climate is often the most important factor for older Americans who decide to relocate, and some of these cities rank among those with the best weather.

Not all cities on this list are retirement destinations. A healthy economy and strong job market can make any city appealing to potential new residents and those looking to start families. In all but four cities on this list, the annual unemployment rate is lower than or equal to the 3.9% national rate. Several of these cities have booming job markets, adding jobs at a faster rate than any other city in their state.

Click here to see America’s fastest growing cities

To determine the fastest growing U.S. cities, 24/7 Wall St. reviewed population change between July 2010 and July 2018 (the latest available data) in every U.S. metro area with data from the U.S. Census Bureau’s Population Estimates Program. Figures on each component of population growth — births, deaths, and international and domestic migration — also came from this report and are from April 2010 to July 2018. Employment change between 2010 and 2018 came from the Bureau of Labor Statistics’ Quarterly Census of Employment and Wages. 2018 unemployment rates came from the Bureau of Labor Statistics’ Local Area Unemployment Statistics. Median household income, poverty rate, SNAP recipiency rate, and demographic data are five-year averages from the U.S. Census Bureau’s 2017 American Community Survey.