exponential decay vs exponential return

exponential decay and exponential return both are nouns.

Word	Noun	Adjective	Verb	Adverb
exponential decay	Yes	No	No	No
exponential return	Yes	No	No	No

As nouns, exponential decay and exponential return are synonyms defined as:

exponential decay and exponential return: a decrease that follows an exponential function

exponential decay (noun)	exponential return (noun)
a decrease that follows an exponential function	a decrease that follows an exponential function