Oxygen Level

The elevation level at my house is about 4600 feet. I have a device that fits over my finger and measures the level of SPO2. I usually have about 91-92%, although I can get the number up to 95% or so when I take deep breaths. One reason I like running is that it automatically puts me into heavy-breathing that gives me more oxygen. During my cruise, I was at sea level, and the device gave readings of about 94-95% while breathing regularly, indicating I was getting about 2-4% more oxygen at the lower level of the cruise. The graph drawn by my TemnID device looks better (more regular) due to my pacemaker. I do though, once in a while, skip beats. I've known about this skipping of beats for over 30 years, and the heart-doctors don't seem concerned about it.

I'm using the pointer finger of my left hand for these measurements. I've tried other fingers and my right hand, and the results are about the same.