The net amount on your dashboard already takes refunds into account.
What net revenue means
Net revenue is your total ticket sales minus any refunds that have already been processed. You don't need to subtract refunds separately, it is already done.
Where to see the breakdown
From your dashboard, you can drill down by event to see gross sales, refunds, and net revenue side by side.
Payouts
The amount available for payout matches your net revenue (minus any payouts you have already taken).