All indentures were for a set period of time, usually ending when the apprentice reached the age of 21, when they were considered a legal adult responsible for their own actions and capable of earning a living. While most apprenticeships began when the person was 13 or 14, those created by the Overseers of the Poor tended to start at much earlier ages. The average age of most poor indentures in Boston during this period was 9 and a half.