..and for the wifi?

[giga89]

Hi,
thank for your job! It's awesome.
But i have a doubt, how to measure wifi bandwitch use?
I tried with a "raw" calculation like this:
sensors:
wifi_out:
friendly_name: "Wifi BW Out"
unit_of_measurement: 'mbit/s'
value_template: {{float(states('sensor.snmp_stats_192_168_10_201_netif_ppp1_curbw_in_mbit)) -float(states('sensor.snmp_stats_192_168_10_201_netif_eth1_curbw_in_mbit)) - float(states('sensor.snmp_stats_192_168_10_201_netif_eth2_curbw_in_mbit)) - float(states('sensor.snmp_stats_192_168_10_201_netif_eth3_curbw_in_mbit)) - float(states('sensor.snmp_stats_192_168_10_201_netif_eth1_curbw_in_mbit))}}

But it dont work. I don't know why but if i create a new entity in my configuration.yaml like this ->
sensors:
wifi_out:
friendly_name: "Wifi BW Out"
unit_of_measurement: 'mbit/s'
value_template: {{float(states('sensor.snmp_stats_192_168_10_201_netif_ppp1_curbw_in_mbit)) }}
entity_id: sensor.snmp_stats_192_168_10_201_netif_ppp1_curbw_out_mbit

the value is always ZERO.
Please help me.

Thank u in advance
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