capable of being rated or appraised.
proportional: ratable distribution of wealth.
Origin of ratable
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
able to be rated or evaluated
British (of property) liable to payment of rates
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Online Etymology Dictionary, © 2010 Douglas Harper