I will track my range and percentage over time.
On a daily basis, my charging limit is set to 80% according to Real-world study for the optimal charging of electric vehicles. I am trying not to get below 20%.
As I live i n Denmark where it is cold in winter, I use Smart Heating in the Stats for Tesla app. I charge 80% at night when the electricity is cheapest (and the CO2 footprint is the least). 45 minutes before driving in the morning Smart Heating warms the car up (cabin and battery); which uses 1% power.
According to tesla-info.com "reports suggest there is an initial drop within the first few months and then the rate of degeneration tails off. A typical scenario is therefore a 5% drop fairly quickly and then a further 5% drop over the life of the car".
April 1, 2020 (42.100 km/26,160 mi):
Data from Stats for Tesla app