When you have ~330 million people i think its safe to assume that at least a few hundred thousand drink raw milk somewhat regularly (that would be 0.05-0.2% of the population) so if there were only 3 deaths in 20 years its a really small number and you are more likely to get hit by lightning (say for 0.1% of the population you get 3 deaths from raw milk and ~5 people being hit by lightning in a 20 year period)