CREATE TABLE table_203_163 (id DECIMAL, "year" DECIMAL, "total" DECIMAL, "serbs" TEXT, "hungarians" TEXT, "germans" TEXT, "romanians" TEXT, "slovaks" TEXT)

what was the first year that the romanian population was less than 51,000 ?
SELECT MIN("year") FROM table_203_163 WHERE "romanians" < 51000
SELECT MIN("year") FROM "table_203_163" WHERE "romanians" < 51000