That's a shockingly low health for a battery with that few cycles. Actually, if you use your computer every day, that's a small number of cycles…

It's 6 years old, it's perfectly acceptable health for a battery that gets use.

2012 MBP here: 87.3% health (6900 mAH as designed, 6021 mAH now) on 871 cycles, 2533 days old. Pretty impressed with it really. I use this Mac a lot.

You keep it plugged in all the time? Do you feel a noticeable drop in battery life? When mine reached those 80% health I felt like it had lost half its battery life or more...

Same here (2013 Retina MBP)

yep late 2013 Retina MBP 15"

mostly plugged in, but I don't have any anxiety when I unplug it

What software are you using to get the percentage? My Early 2015 MBP is on around 300 cycles but not sure how to get the percentage.

Late MBP 2013 at 87% health capacity (481 cycles)

15" Retina MBP late 2013 with original battery. System reports 142 cycles (I mostly use it at a desk) and condition Normal.

Unfortunately it's not at all normal, it's swollen to the extent that the bottom of the case is slightly warped and the macbook will no longer sit flat. It's also affected the trackpad which doesn't click very well any more. I noticed these things a while back but didn't realise that the battery was the cause until I opened it up a couple of days ago to clean it out (something I do once or twice a year).

Now awaiting a battery replacement kit from iFixit and not looking forward to removing the old one. Probably going to try the dental floss method someone mentioned above (very, very carefully and far away from anything flammable).