Table 4. Estimated total hospitalized cases of pneumonia averted by PCVs, United States, 1997–2019*.

Time period	Estimated hospitalizations					Total hospitalizations averted
	Observed, with vaccination			Expected without vaccination
	Minimum	Maximum		Minimum	Maximum	Minimum	Maximum
Pre-PCV era: 1997–1999	NA	NA		339,474	525,675	NA	NA
PCV7 era: 2000–2009†	959,543	1,336,673		597,479	1,822,591	222,611	490,043‡
PCV13 era: 2010–2019§	382,182			598,484		216,303

*PCV7 was approved for use in the United States in 2000; PCV13 was approved for use in the United States in 2010. NA, not applicable; PCV, pneumococcal conjugate vaccine; PCV7, 7-valent PCV; PCV13, 13-valent PCV.
†Averted hospitalizations during PCV7 era are shown as the difference within the same study with minimum based on Simonson et. al. (24) and maximum based on Grijalva et al (29) (Appendix Table 14).
‡Grijalva et al (29) reported a change in hospitalization rate; as a result, no observed and expected values were generated.
§Values based on calculations using a single data point.