I can tell you: In 1963, just before a vaccination for measles existed, there were (IIRC) 400-500 deaths in 3-4,000,000 cases. That would be a death rate of .01%. Ten times less than what we see for flu these days. That is according to cdc.gov.
Bingo! Give that man a gold star. If I can figure out a way to post the graph from the CDC website that shows the death rate virtually bottoming out in the mid-40's - fully 18 years before the introduction of the vaccine, I will do so. Clearly shows that the vaccine merely piggybacked on the natural declination and falsely claimed credit for it. Same thing with Diphtheria.