CREATE TABLE table_12951 ("Player" TEXT, "Country" TEXT, "Year ( s )  won" TEXT, "Total" FLOAT, "To par" TEXT, "Finish" TEXT)

What year did the United States win with a total of 278?
SELECT "Year(s) won" FROM table_12951 WHERE "Country" = 'united states' AND "Total" = '278'
SELECT "Year(s) won" FROM "table_12951" WHERE "Country" = 'united states' AND "Total" = '278'