CREATE TABLE table_203_33 (id DECIMAL, "conference" TEXT, "date" TEXT, "place" TEXT, "attendance" DECIMAL, "archive of presentations" TEXT)

which wikimania conference has the least number of attendees ?
SELECT "conference" FROM table_203_33 ORDER BY "attendance" LIMIT 1
SELECT "conference" FROM "table_203_33" ORDER BY "attendance" NULLS FIRST LIMIT 1