Why warship ratings are planning averages

A cake divided into nominally equal calorie portions introduces the problem, since the icing makes each slice different. The printed figure is still useful as a common average for planning. That everyday mismatch frames the Royal Navy's rating system. A first, second, or third rate belonged to an administrative standard, but no table could capture every gun, crew allocation, or material difference aboard a particular ship. The same warning applies to every later fleet total and rating comparison.