Get avg parameter with zabbix-get?

[tool]

Hi, can i get avg of some key with zabbix-get? For e.g.

zabbix-get -s -p -k net.if.in[eth1,bytes]?

Or maybe you can help with retrieve of avg data net.if.*

I need this values for some actions in my script, if net.if.in[eth1, bytes].avg(300) > net.if.in[eth1,bytes] * 0.8 than do some actions.