Pulse oximeter reading months after covid

[tulips27]

I had covid months and months ago, no long-lasting effects [TOUCH WOOD] apart from a slightly reduced sense of smell/taste. But pre-covid I would get a reading of 100 or 99 on the pulse oximiter (I always had one because of asthma). Since covid, the reading is usually around 96 or 7. Yes I appreciate that is a small difference etc. and not concerning on its own, but I'm just wondering if that indicates I've lost some lung function/efficiency? Is there something I should do about it or just forget it? Thanks.

I think similar - I had covid quite badly in December 2020, no hospital admission but was the worst I'd felt.
Before covid, my lung capacity felt good, I did yoga breathing exercises and generally would be 99-100%, during covid it did dip down worryingly, and post covid I can usually get a 96-97 reading plus I have to work at the deep breathing exercises so I do feel I lost some lung capacity / efficiency from covid.

It can be recovered , I have lung disease and readings vary from 96-99, usually on higher end when I exercise and eat well.