percent sign vs graphic symbol

percent sign and graphic symbol both are nouns.

Word	Noun	Adjective	Verb	Adverb
percent sign	Yes	No	No	No
graphic symbol	Yes	No	No	No

As nouns, graphic symbol is a hypernym of percent sign; that is, graphic symbol is a word with a broader meaning than percent sign:

percent sign: a sign (`%') used to indicate that the number preceding it should be understood as a proportion multiplied by 100
graphic symbol: a written symbol that is used to represent speech

Other hypernyms of percent sign include character, graph, grapheme.

percent sign (noun)	graphic symbol (noun)
a sign (`%') used to indicate that the number preceding it should be understood as a proportion multiplied by 100	a written symbol that is used to represent speech