People like to ignore the fact that Janet's sales are lower than the other divas (minus Whitney) because she didn't release as many products as the other.While Mariah & Madonna were releasing albums, soundtracks, & remix albums every year, Janet was releasing an album every 3-4 years.Those soundtracks & compilations add to their totals to help them get to 200-300 million records sold. They didnt necessarily "sell more", they released more albums. Take away their extra GH and remix albums and soundtracks and you'll see Janet's sales are right on par with them, aside from the fact that she's horribly undercertified.