This bar chart shows the yearly count of whooping cough cases in the U.S. since 1992, when more than 100,000 cases were recorded. The yearly figure spikes to nearly 300,000 in 1934, then starts declining in earnest in the 1940s, when the vaccine was introduced. Counts get as low as 1,010 in 1976, but start ticking up in the 1980s. Nearly 50,000 cases were counted in 2012, which wasn't the norm, but cases in 2024 and 2025 have exceeded 25,000 in each year.