Just as on the demand side, the position of the supply can shift, say from a change in the price of a productive input or a technical improvement. The Law of Supply states that, in general, a rise in price leads to an expansion in supply and a fall in price leads to a contraction in supply.
Puberty takes place over a number of years, and the age at which it starts and ends varies widely. It generally begins somewhere between the ages of 7 and 13 for girls, and somewhere between the ages of 9 and 15 for guys, although it can be earlier or later for some people.
Late bloomer can refer to children who suffer from delayed puberty, who are late in reaching their full height. W. B. Yeats (age 30), Pierre Trudeau (age at least 28), Mark Twain (age 34), and Johann von Goethe (age 39) are all late bloomers in this last sense. In most public educational systems, children and adolescents of the same age are put in the same classes.