I have some trouble understanding the measure Functional Health (average) when it comes to charting.
Here's our business case; we have to build a common chart for different system profiles to show our customers the "availability" of the services based on this metric. Users will be able to select their desired timeframe to watch how their service is doing.
As per my understanding, "functional health - average" metric will show an unweithed media for the selected timeframe. So, I select a one month timeframe to picture a service. I see the points for each day; I pick one of the days and the chart says "0.31%" unavailability for day "X" at 00:00. I want to further analyse this data and change the timeframe for that very day "X", selecting 0:00 to 23:55. The unavailability shown for that day is 21.4%. When hitting the point for 00:00 time, the data shown is 29.3%, when expected was the same "0.31%" from the previous timeframe selection.
How is that supposed to happen? Am I missing differences between both timeframes? Is the metric affected by the selected timeframe? No additional parameters have been modified in the chart. Or simply is it that we cannot expect to extract daily information for our customers from a dashboard with a month timeframe?
See screenshots for further information.
I can explain why on the two charts, the Jan 15 00:00 data point is showing different values, and that's because on the first chart Jan 15 00:00 data point represents timeframe Jan 15 00:00 - Jan 16 00:00, whereas on the second chart it represents Jan 15 00:00 - Jan 15 01:00, so the percentage of failed transactions out of total transactions would be different for 1 hr vs 1 day.
However, I would've expected the big number in the top right corner on the 2nd chart to be 0.31%. The average for the day should still be 0.31% as indicated by the data point on the first chart. I have no answer for this one.