Upon returning to a document set previously partially annotated, moving around, and annotating a few more documents, the number of documents reported in the statistics pane far exceeds the number of documents in the annotation set. I suspect some of the other stats may be artificially increasing as well, but I'm not positive of that.
Example: If I return to a fully-annotated set of documents and look at stats, it accurately reports 70 documents annotated. If I then advance to the next document, it suddenly reports 210 documents annotated.
Upon returning to a document set previously partially annotated, moving around, and annotating a few more documents, the number of documents reported in the statistics pane far exceeds the number of documents in the annotation set. I suspect some of the other stats may be artificially increasing as well, but I'm not positive of that.