All standard variables are based on calendar dates and century month codes are given in the Ethiopian Calendar. The Ethiopian year consists of 365 days, divided into 12 months of 30 days and one month of 5 days (6 days in a leap year). Ethiopia's new year falls on September 11and ends the following September 10 according to the Gregorian calendar. Before the production of any indicators with these data the Ethiopian calendar was converted to the Gregorian calendar but conserving the Ethiopian year; however, the Ethiopian first month is considered in the logic as January, the 2nd as February, etc. For dates including year, month and day the conversion is precise since both calendars have 365 or 366 days; for dates including only year and month, the 13th month was included in December.