CREATE TABLE table_49572 ("Location" CLOB, "Year" FLOAT, "Champion" CLOB, "Runner-up" CLOB, "Score" CLOB)

When was the earliest year that Guillermo Vilas was the runner-up?
SELECT MIN("Year") FROM table_49572 WHERE "Runner-up" = 'guillermo vilas'
SELECT MIN("Year") FROM "table_49572" WHERE "Runner-up" = 'guillermo vilas'