allotment vs percentage

allotment and percentage both are nouns.

Word	Noun	Adjective	Verb	Adverb
allotment	Yes	No	No	No
percentage	Yes	No	No	No

As nouns, percentage is a hypernym of allotment; that is, percentage is a word with a broader meaning than allotment:

allotment: a share set aside for a specific purpose
percentage: assets belonging to or due to or contributed by an individual person or group

Other hypernyms of allotment include part, portion, share.

allotment (noun)	percentage (noun)
the act of distributing by allotting or apportioning; distribution according to a plan	assets belonging to or due to or contributed by an individual person or group
a share set aside for a specific purpose	a proportion in relation to a whole (which is usually the amount per hundred); ten percent