Janet's top-selling digital tracks:
Feedback - 822,000
That's the Way Love Goes - 242,000
All for You - 235,000
If - 212,000
Call on Me - 179,000
http://www.billboard.com/column-chartbeat/ask-billboard-katy-perry-christina-aguilera-1004100889.story#/column/chartbeat/ask-billboard-sugarland-s-sweet-success-1004124554.story