ratability vs rateability

ratability and rateability both are nouns.

Word	Noun	Adjective	Verb	Adverb
ratability	Yes	No	No	No
rateability	Yes	No	No	No

As nouns, ratability and rateability are synonyms defined as:

ratability and rateability: the state of being liable to assessment or taxation

ratability (noun)	rateability (noun)
the quality of being capable of being rated or estimated	the state of being liable to assessment or taxation
the state of being liable to assessment or taxation