The June 7 spike in sales is the week when Taylor posted that clip of her singing Fight Song with Rachel backstage after her Pittsburgh concert. That clip already has 1m likes on Instagram.
The June 14 spike in sales is the week when Taylor and Rachel performed Fight Song at her Philly Concert and later tweeted about it. Taylor's instagram pics of this duet have already each accrued more than 1 million likes in 2 days!
Fight Song has gone number 1 on iTunes. Rachel has responded by thanking Taylor for her support and generosity on twitter.