They spent 480mln and they sold players for 219mln. So it's 261mln roughly
Arsenal spent 293mln but sold for only 10mln
Chelsea spent 382 but sold for 332mln
City spent 206 but sold for 70mln
United spent 250 but sold for 75mln
----
For a comparison:
Juve spent 137mln and sold for 84mln.
Napoli spent 115mln and sold for 126mln
Milan spent for 164mln and sold for 170mln
Inter spent 92mln and sold for 48mln
Roma spent 63mln and sold for 50mln
Although, have in mind that these numbers are taking into account loans paid this year, but not the whole deal, even if it's loan with obligation. So the number in some (many) cases is higher. For example, Kiwior accounts for 2mln sale, but he's on obligation for 17mln extra.
But yeah, bottom line, this is fucking crazy.