Monitoring Uptime Across Network

Anyone know how to do this?? Looking for a percentage based on all AP’s in the network. any help would be greatly appreciated.

There is an oid for uptime,

/system resource> print oid
uptime: .1.3.6.1.2.1.1.3.0

that reports time when router is uptime.
I’m not sure there is an option in Dude to make percentage for this graph.