Finished Measurements:
6 months: 17.75in
12 months: 18.75in
18 months: 19.5in
24 months: 20in

Yarn is listed in pattern as 226 yds per skein

6 months requires 2 skeins in main color, 1 skein contrast color
12, 18 & 24 months require: 3 skeins main color, 1 skein contrast color