WHAT'S BEHIND THE FALLING U.S. BIRTHRATE? May 13, 2021 · As reported by the Center for Disease Control, the number of births has been dropping for several years, with a 4% decline between 2019 and 2020. A 4% decline is significantly higher than the year-to-year declines recorded for prior years—between 2015 and 2019 yearly declines were about 1-2% between 2015 to 2019.