CREATE TABLE table_204_298 (id DECIMAL, "year" DECIMAL, "competition" TEXT, "venue" TEXT, "position" TEXT, "event" TEXT, "notes" DECIMAL)

before the 2000 olympic games what was johanna 's fastest 200m time ?
SELECT "notes" FROM table_204_298 WHERE "year" < 2000 AND "event" = '200 m' ORDER BY "notes" LIMIT 1
SELECT "notes" FROM "table_204_298" WHERE "event" = '200 m' AND "year" < 2000 ORDER BY "notes" NULLS FIRST LIMIT 1