7.5 trillion USD is traded on the average every day on Net-Net basis while around 9.8 trillion USD is traded on average every day on Net-Gross basis.
So in simpler language a daily average of around 9.8 trillion is traded daily but after certain deductions and adjustments are made it comes down to 7.5 trillion USD daily.
Net-Net means the figures has been adjusted for local and cross-border inter-dealer double-counting, i.e. “net-net” basis.
Net-Gross: 9.8 Trillion USD
Net-Net: 7.5 Trillion USD
https://www.bis.org/statistics/rpfx22_fx.htm