James City-area historical tornado activity is slightly below Pennsylvania state average. It is 37% smaller than the overall U.S. average. On 5/31/1985, a category F4 (max. wind speeds 207-260 mph) tornado 9.9 miles away from the James City place center killed 4 people and injured 40 people.
Maasai - Age-sets. Introduction. The basic Maasai political and social structure is their rigid system of age-sets (or age grades; strictly-speaking, an age-grade is a stage within the age-set). These apply primarily to men; women automatically become members of the age-set of their husbands. Under this system, groups of the same age (give or take five years or so) are initiated into adult life during the same period. The age-set thus formed is a permanent grouping, and lasts throughout the life of its members.
The calculation for an age-specific rate is the same as for a crude rate. Crude rates are valuable for comparing similar population of different sizes, but the word, similar is a key concept, because crude rates can be misleading when comparing rates for populations with different age compositions.