I have been working on an analysis tool to try and get the max number of pulses in a month. This has been very difficult for me. I can not seem to find an example that does a max by month. Even some examples within the community are not working correctly. Does anyone have any examples or can point me in a direction for a good working sample?

For context; I am trying to get the max pulse in a month from 3 separate water meters. I will then create a dashboard widget.