progressiveness vs progressivity

progressiveness and progressivity both are nouns.

Word	Noun	Adjective	Verb	Adverb
progressiveness	Yes	No	No	No
progressivity	Yes	No	No	No

As nouns, progressiveness and progressivity are synonyms defined as:

progressiveness and progressivity: advancement toward better conditions or policies or methods

progressiveness (noun)	progressivity (noun)
advancement toward better conditions or policies or methods	advancement toward better conditions or policies or methods