CREATE TABLE table_9906 ("Generation" TEXT, "Birthday" TEXT, "Birthplace" TEXT, "Blood Type" TEXT, "Agency" TEXT)

What generation is the member born on 1992.12.23 in?
SELECT "Generation" FROM table_9906 WHERE "Birthday" = '1992.12.23'
SELECT "Generation" FROM "table_9906" WHERE "Birthday" = '1992.12.23'