User blog comment:JoshuaJSlone/Template:Age in years, months and days/@comment-131168-20140519114717

A similar template, in that it probably has limited use and is about age. This one will report age in years and decimal points of years. Best only if you want the decimal points--it takes the age in days and divides by an average year length of 365.242 days, so if you're just going by whole numbers you can't count on it increasing a person's age exactly on their calendar birthday. It's Template:AgeDecimal and you can read more detail on it there, but in short you can get an age with the default 1 decimal point like, or with 2 like.