Nobody knows exactly apart from Collecott the finance director. When we got the NFL contract Ally Gold stated that Spurs received a stadium rental fee plus profits from food/drink sales and at that all the gate receipts were kept by the NFL so I would expect probably a similar arrangement for concerts , I think that's what happened at Wembley we paid them a rental fee , we kept all the gate money and they got food/drink sales.
The accounts do not specifically state how much is made from concerts exclusively, it lumps a whole load of revenue together . In the last accounts shown under "other revenue" which was £64 million up from £55.4 million the previous year, the total includes revenue from non-football events, membership fees, stadium tours, sky walk, conference and business events, pre season tour , matchday catering and F1 drive. It's a nice total but still way behind what the Mens PL squad brings in with gate receipts, TV money and PL prize money and this season Europa money. etc.