Nearly three-quarters of counties in the United States experienced a spike in deaths last year, according to newly released Census data. More than 73 percent (2,297) of U.S. counties experienced a “natural decrease” in 2021, up from 45.5 percent in 2019 and 55.5 percent in 2020 at the height of the COVID-19 pandemic, according to the U.S. Census Bureau’s…