I asked grok about this, and it's answer was interesting. I'd be really interested in seeing autism numbers before and after 1971. Especially since the time-frame fits my life, and my autism. I'll have to research that deeper.

The measles vaccine was combined into the MMR (measles, mumps, and rubella) vaccine in 1971 in the United States. Here’s the timeline: The first standalone measles vaccine, a live attenuated version developed by John Enders and colleagues, was licensed in 1963. It was effective but required separate administration from other vaccines. Meanwhile, vaccines for mumps (licensed in 1967) and rubella (licensed in 1969) were also developed. In 1971, Merck introduced the MMR vaccine, combining all three into a single shot, streamlining immunization efforts. The U.S. CDC adopted it as the standard, replacing the individual measles vaccine in routine childhood schedules by the mid-1970s. The exact date of the MMR’s debut is often cited as 1971, with no specific day widely noted, but it marked a shift to combination vaccines for efficiency and broader protection.