APA Style (7th ed.)
If you're deciding whether to use "percent" or "%", please "use the percent symbol and currency symbols only when they are accompanied by a numeral; also use them in table headings and in figure labels and legends to conserve space" (American Psychological Association, 2020, p. 187). Use "percentage" when a numeral isn't provided e.g., 3% versus "a low percentage".
Reference
American Psychological Association. (2020). Publication manual of the American Psychological Association (7th ed.). https://doi.org/10.1037/0000165-000
