A rower may compete as a Master from the beginning of the year during which he or she attains the age of 27. A rower shall be placed in the age category corresponding to the age as of December 31, 2010. A crew’s age is determined by rounding down to the highest contained integer of the aggregate mean age of its rowers (For example, the age of a crew whose rowers have a mean age of 54.9 is 54, and thus is a D category boat). Age categories: A – Minimum age 27 or more B – Average age 36 or more C – Average age 43 or more D – Average age 50 or more E – Average age 55 or more F – Average age 60 or more G – Average age 65 or more H – Average age 70 or more I – Average age 75 or more J – Average age 80 or more