That would be an indication, but note that the size of the IO blocks also plays a role.
I would also include the throughput (throughput.usage.average) and the latency (totalReadLatency.average,totalWriteLatency.average).
That should give a more complete picture.
Ideally you could use Get-EsxTop and run it for a couple of minutes.
Do this several times during the day.
The esxtop counters are over smaller intervals and they show (mostly) the same metrics as you see in the esxtop utility.