I'm trying to use Analog Statistics on a calculated tag. The minimum and maximum values for yesterday are always the same. The calculated tag is combining a low and high register value for flow pulses. You can see the direct reading of the low register tag (2nd pic) shows yesterdays minimum and maximum values correctly. I also attached the calculation tag and expression I used. Why do the statistics not work for the calculation tag? Also, why does the Historical Data Viewer not represent the true reading of the calculation? Days will go by on the Data Viewer before there is a change and it is not correct.

Have you setup up logging (tied a Historian) to the History Statistics tags? These are not enabled to be logged by default , which explains why the HDV does not give you any useful data--there isn't any.

As to why your minimum and maximums are not working, you could try building your own History Statistics tags as needed. I don't like how the Analog Statistics tag generates an insane amount of disabled tags for each instance.