Table schema:
CREATE TABLE table_name_79 (year VARCHAR, apparatus VARCHAR, competition_description VARCHAR, rank_final VARCHAR)

Question: What is Year, when Competition Description is "U.S. Championships", when Rank-Final is less than 3, and when Apparatus is "All-Around"?
SQL: SELECT year FROM table_name_79 WHERE competition_description = "u.s. championships" AND rank_final < 3 AND apparatus = "all-around"