STUDIO ALBUMS   Janet Jackson (1982):   US: 400,000. Worldwide: 700,000. (CSPC: +900,000).   Dream Street (1984):   US: 250,000. Worldwide: 400,000. (CSPC: +450,000).   Control (1986):   US: 6,388,018. UK: 575,000. Worldwide: 14,000,000. (CSPC: 16,400,000).   Janet Jackson's Rhythm Nation 1814 (1989):   US: 8,489,047. UK: 425,000. Worldwide: 14,000,000. (CSPC: 1