data vs accumulation

data and accumulation both are nouns.

Word	Noun	Adjective	Verb	Adverb
data	Yes	No	No	No
accumulation	Yes	No	No	No

As nouns, accumulation is a hypernym of data; that is, accumulation is a word with a broader meaning than data:

Other hypernyms of data include aggregation, assemblage, collection.

data (noun)	accumulation (noun)
a collection of facts from which conclusions may be drawn	the act of accumulating
	several things grouped together or considered as a whole
	(finance) profits that are not paid out as dividends but are added to the capital base of the corporation
	an increase by natural growth or addition