I have found this to be somewhat troublesome up until now.
Alot of fluctuations in my measurements were due to the following reasons:
1. Erection quality - My erection goes down after 1 to 5 seconds of no stimulation. (Is this normal btw?)
2. Angle - If I push my penis forward (or ‘down’) I get a higher measurement than when I pull it towards my belly.
3. Amount of pressure - Pushing in the ruler too much or too little for (Applies for both BPEL and NBPEL measurements)
4. Sitting/standing - Somewhat the same as angle.
5. Curve - When I do make measurements I make sure my penis is straight out, this might fluctuate as I may use more/less curve at different times.
6. Ruler position
I also notice the pubic bone goes down towards my penis thus when I place the ruler closer to the shaft I get a higher measurement bone pressed.
I think it’s very important to measure CORRECTLY the same time over and over again if you are serious about tracking gains. Because I can easily gain or lose 1/4” to 1/2” due to measuring wrong.
I thought I was gaining :) And I probably did, but I will discard these gains for now since I developed a measuring method for myself which makes it more consistent and fair. So find out what works for you and once you have, don’t measure too often!