I recently had the idea to add up how much time I've spent playing Bethesda RPGs according to Steam. My list:
Elder Scrolls IV: Oblivion: 991 hours
Elder Scrolls V: Skyrim: 761 hours
Fallout 3: 1100 hours (approximately, only one I don't have on Steam)
Fallout: New Vegas: 1000 hours
Fallout 4: 598 hours (and counting, close to finishing MQ not NEARLY close to finishing the game)
TOTAL: 4450 hours or 185 days of continuous gameplay. Worst part: I have no regrets