122. Item l l. Age at last birthday.-Enter the age of the person at his last birthday as of the date of your call. For persons 1 year old and over, this question calls for the age in completed years at last birthday.

123. Ages of infants.-The entry for children less than a year old should indicate the month of birth. For example, the entry for a child born in March, 1950, should be "March." It is permissible to abbreviate where necessary in entering the name of the month, for example "Dec." for December.