During "The Year of Hell" (the ultimate reset-button episode), various changes in the timeline occur. This is due to Annorax' manipulation of the space-time continuum, by use of his weapon ship.
At the end of the YoH, part 2, Captain Janeway crashes Voyager into Annorax' ship and apparently erases it from existence---or at least erases the entire history of the "Year of Hell."
Annorax is shown with his wife in the final scene. He is working on temporal-incursion calculations.
This is confusing to me. His main goal throughout the episode is to restore his wife, and, through the destruction of his ship, this occurs. So, is Annorax working on calculations because the size of the Krenim Imperium (in his eyes) is substandard? This seems to be the case, as the attitude of the (same) Krenim officer is different in his dealings with Janeway. Perhaps this is caused by a sort of reservation on the part of the Krenim due to having relatively low numbers.