CREATE TABLE table_203_81 (id DECIMAL, "date" TEXT, "constituency" TEXT, "gain" TEXT, "loss" TEXT, "note" TEXT)

what was the first gain on may 30th , 1963 ?
SELECT "gain" FROM table_203_81 WHERE "date" = '30 may 1963'
SELECT "gain" FROM "table_203_81" WHERE "date" = '30 may 1963'