We have found great use for the PI Point Value Retrieval Methods available for PI Point attributes. One such use is for displaying downtime percentage for numerous assets on a PI Vision page. The downtime percentage can be calculated for any interval by taking the average of a PI tag that reads 1 when the asset is down, and 0 when running.
For digital PI Points, the PI Point Value Retrieval Methods don't work because the tag is treated as non-numeric in AF, even though it's just a mapping from integers to strings. To implement the solution above, we typically have to create AF Analyses that read the digital PI Points and write 1/0 integer outputs to new tags, and then assign value retrieval summaries to the new tag.
It would be easier and more convenient to enable this feature on digital PI Points by converting the states to their corresponding integer enumeration before summarizing.