bridge tx/rx numbers double WiFi numbers

Hi. Using Capsman. I’ve noticed this before, but just wanted to ask..

when the internet is being used, and the Tx for the WiFi (virtual i/f from capsman v2) is showing 10Mbps to a laptop, and the PPPoE Internet on eth1-gateway is Rx for the same connection @10Mbps, then why does the bridge, which contains wifi and only eth2 - 5, show 20Mbps Tx?

anyone?