Why Did Lightning Strike Deaths Decline So Dramatically?

Decline in rural population and mechanization of agriculture?  Maybe:

I spoke with Ronald Holle, a meteorologist who studies lightning deaths, and he agreed that modernization played a significant role. "Absolutely," he said. Better infrastructure in rural areas—not just improvements to homes and buildings, but improvements to farming equipment too has—made rural regions safer today than they were in the past. Urbanization seems to explain some of the decline, but not all of it.
"Rural activities back then were primarily agriculture, and what we call labor-intensive manual agriculture. Back then, my family—my grandfather and his father before that in Indiana—had a team of horses, and it took them all day to do a 20-acre field." Today, a similar farmer would be inside a fully-enclosed metal-topped vehicle, which offers excellent lightning protection. Agriculture has declined as a percent of total lightning-death-related activities, as the graph below shows, but unfortunately it does not show the per capita lightning-death rate of people engaged in agriculture.

 The correlation on that first graph is awesome.  I don't know if the "not working outside all day means fewer lightning strikes" explanation is accurate, but it makes sense to me.  One other thing I didn't see mentioned in the story is better weather forecasts.  It is commonplace to see forecasts call for thunderstorms arriving around noon (for example), and they are fairly accurate.  If you were in the back forty back in the day and a fast moving storm came in, you might not be able to head for cover.  There wasn't a weather forecast saying, "Nasty weather around noon."  I'd figure that might make some difference.