Although Apple posted quarterly net profit of $13 billion for its 2015 second quarter earlier this week, the company saw digital sales fall by 4% in Q2 15 and 5% in the first six months of its 2015 financial year.

Apple disclosed the iTunes Store’s waning performance in its official US Securities Exchange Commission (SEC) report, filed for the second quarter ending March 28, 2015.

Apple’s 27% revenue growth overall was fueled by record second quarter sales of iPhones ...