The slide comes from an RIAA presentation leaked to Torrentfreak, with researcher NPD Group breaking out the categories. And it shows that most swapping happens offline, with swapped hard drives and burning and ripping of others' collections key culprits. All of which is technically illegal, but a legal nuance to those doing it (go ask a non-industry friend to confirm this).
Specifically, if illegal trading accounts for 65 percent of all acquisition, than 46 of that 65 is coming from swapped drives and discs. Which amounts to 70.7 percent of the illegal swapping pie.
And, P2P amounts for less than 25 percent (ie, 23 percent) of illegal acquisition. And, that's an amount that keeps shrinking, thanks partly to continued growth at Spotify, and more importantly, YouTube. According to separate research presented on the Google channel, roughly 40 percent of all YouTube views come from music videos, a massive displacement against downloads.