You're almost right but what you need to keep in mind is the following:
Reducing your value
- There are actually more circulating COSS, c.98m, not sure why CMC is stating that figure but we have the number of circulating COSS each week in our dashboard, reducing a bit this number
- Trading fees are degressive according to the amount you're trading, you can find the exact breakdown in their whitepaper

Increasing your value
- Trading fees are paid twice (for the buyer and the seller), so you need to multiply by 2
- Fees will not just depend on the volume: you receive dividends for fees for ICOs, for withdrawals, for fiat deposit in the future...