For example, the average age of the onset of menstrual periods in girls was 15 in 1900. By the 1990s, this average had dropped to 12 and a half years of age.uberty facts. 1  Puberty is the period of sexual maturation and achievement of fertility. 2  The time when puberty begins varies greatly among individuals; however, puberty usually occurs in girls between the ages of 10 and 14 and between the ages of 12 and 16 in boys.
Herbert Hoover was the president of the U.S. when the great depression began in 1929.
Americaâs greatest depression fighter was Warren Gamaliel Harding. An Ohio senator when he was elected president in 1920, he followed the much praised Woodrow Wilsonâ who had brought America into World War I, built up huge federal bureaucracies, imprisoned dissenters, and incurred $25 billion of debt.