How to display throughput with multiple interfaces?

how to display throughput with multiple interfaces?

I tried mangle rules with filtering on input inteface and output interface;
I marked in-interface as UPLOAD and out-interface as DOWNLOAD.

But I download with speed of 800Kbps but if I go to mangle rules and watch statistics (via winbox) I don’t see that, but lower speeds…

How would you watch router and throughput on individual interfaces?

/ip firewall mangle print

1 chain=prerouting in-interface=AP action=mark-connection new-connection-mark=AP_upload
passthrough=yes

2 chain=prerouting connection-mark=AP_upload action=mark-packet new-packet-mark=AP_upload
passthrough=yes

3 chain=forward out-interface=AP action=mark-connection new-connection-mark=AP_download
passthrough=yes

4 chain=forward connection-mark=AP_download action=mark-packet new-packet-mark=AP_download
passthrough=yes