6-9 MONTHS 1 9-12 MONTHS 1 18-24 MONTHS 1 2 YEARS 2 3 YEARS 4 4 YEARS 6 5 YEARS 7 6 YEARS 6 7 YEARS 5 8 YEARS 7 9 YEARS 5 10 YEARS 4 11 YEARS 6 12 YEARS 6 13 YEARS 5 14 YEARS 3 15 YEARS 3