As a partner I added Shipment statistics numerous times and now as a customer find this extremely useful.
In addition to Total volume, Total weight, Nr of lines, Nr of units we also added:
From zone and To zone. These relate to lowest and highest alphabetic zones we expect to pick from, based on the fixed locations of items on the shipment. This helps with work template filtering. I can tell whether a shipment will be picked from a single or multiple zones, and generate work with the appropriate steps.
We also added Work statistics, all the above to the work header, with the addition of From/To location, based on the locations on the pick lines. As per Franz earlier suggestion, these are all Initial values, generated once (with no noticeable overhead) and not maintained ongoing.
Together this is extremely powerful in being able to assign shipments to wave templates and drive work templates off the shipment stats. From/To location/zone on the work then aids cluster building for efficient picking.
However in addition to being useful for the above functionality, we use these statistics endlessly in filtering, grouping, reporting, issue diagnosis, performance monitoring etc. They are so very use in many ways - far more than might originally be apparent.