For those who remember the old website widgetheads.net, you may remember the author of that site kept an Excel spreadsheet of the entire DL fleet. Since that website went down, I've been keeping that spreadsheet up to date through a combination of threads and wikis here, occasionally airliners.net, DL's & OO's quarterly reports, lots of hours staring at Flightaware, and my own research. I'll be starting a new job in a couple of weeks that involves no travel, so I don't know if I'll be updating it much (or at all), but I figured I'd share what I have in case it's useful to anyone. You're more than welcome to do what you want with it as long as you don't make money off of it. Comments, corrections, etc. are welcome. Enjoy!

(NB: the following link lists the fleet as of Dec 31, 2020. For an updated version of this sheet, see the Wiki.)
Link: https://drive.google.com/file/d/1Wm3...ew?usp=sharing

(Note: I recommend downloading the sheet and looking at in Excel instead of Google's viewer.)