Wikipedia does not currently have an article on "year-over-year", but our sister project Wiktionary does:

Read the Wiktionary entry on "year-over-year"

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• Search for Year-over-year in Wikipedia to check for alternative titles or spellings.
• Start the Year-over-year article, using the Article Wizard if you wish, or add a request for it; but please remember that Wikipedia is not a dictionary.