CREATE TABLE table_203_634 (id DECIMAL, "date" TEXT, "venue" TEXT, "score" TEXT, "victor" TEXT, "comments" TEXT, "match reports" TEXT)

in which year did rugby union matches between new zealand and wales occur most frequently ?
SELECT "date" FROM table_203_634 GROUP BY "date" ORDER BY COUNT(*) DESC LIMIT 1
SELECT "date" FROM "table_203_634" GROUP BY "date" ORDER BY COUNT(*) DESC NULLS LAST LIMIT 1