There are several different charts regarding ideal weight and weight ranges, and much depends on which chart is used. I am thin and toward the low end of most charts, but for most North Americans, especially those over 50 yr. old, the lower ranges on the charts seem unreachable.
In this country in the 1950s and 1960s (when I was very young), a great many adults, male and female, were of a size and weight that would now seem abnormally thin to many people.