Video games on a shelf at Waupun, Wisconsin, to borrow free
E
E
E
E
E
E10+
E
E
E
E
E
T
E
E
E
E
E
E
T
E
E10+
T
E
E
E
E10+
E
E
E
T
E
E
E
Copies per library (table)
Each change is stamped with the snapshot that saw it; it happened since the snapshot before (hourly for copies already moving, every 4 hours for everything else).