Interesting. Would call where you grew sparely populated?

How about extremely sparsely populated.

>I don't know where you were

Massachusetts, South Florida, other places east of the Mississippi.

The area is now called Santa Clarita, California. The area was then a clump of bedroom communities that may have totaled about 50 thousand people. Some farmland was still cultivated then (the aroma of the onion harvest is a childhood memory), sheep were even grazed. But there were tracts of houses and the tracts were already closely spaced enough to support three significant high schools. Even from a jet you should have known you were flying over a populated area by looking out the window.

Thanks. Roughly how many sonic booms did you hear during your time there?

My personal recollection is, there were two or more a year. There may have been less in the seventies. In any case more frequent than the minor earthquakes one endures everywhere in California. I was there from age 3 to age 18.