Here's how Under Armour grew into a $15 billion athletic-apparel empire

When Under Armour was founded in 1996 it made $17,000 in annual revenue. In 2014 it made over $3 billion with a market cap that's swelled to $15 billion.

Founder and CEO Kevin Plank has used breakthrough technology, celebrity endorsements, and clever product placement to make Under Armour a force in the athletic-apparel industry.