Uptime report shows percentage of time when a particular resource was Ready within a given timespan.
Precise formula that calculates the Uptime is as follows
For multi-instance resources (such as Azure Cloud Service Roles), when at least 1 Ready instance is detected, the resource is considered to be UP for purposes of Uptime report
For single-instance resources (most others), when the resource Status is Ready, it is considered to be UP for purposes of Uptime report
For each time span, CloudMonix calculates number of UP results vs. number of total measurements. This number is presented as the Uptime percentage on the Uptime report