year-to-year
/ˌjɪətʊˈjɪə/ /ˌjəːtʊˈjəː/adjective
Relevant or relating to successive years; especially determined by comparing results or figures from successive years.
Origin
Mid 19th century; earliest use found in Isaac Taylor (1787–1865), writer on theology, artist, and inventor. From year + to + year, after from year to year.