How to interpret Measure-VM cmdlet output

Hi guys, 

I went through a number of articles related to the resource metering and VM-Measure cmdlet but still struggling to interpret an output related to disk usage.

For example the one below: 

AggregatedAverageNormalizedIOPS is possibly just an average IOPS.

But what about the other three objects? I mean what those values mean in front of each of them?

Thanks.