Don't worry bout it
.
My 6+ was 103% design capacity (coconutBattery) when I bought it. After 240+ cycles it was at 99% when I sold it to Apple.
My 6s+, when I purchased it in May 2016, was 96% with 0 cycles! This bummed me out, but, after almost 1.7 years of ownership, the battery is still 93-95% with 220+ cycles and lasts as long as ever.
These posters are 100% right. Only check a few times a month, for fun only. Your battery design capacity should only be checked at true 100% charge - it can have a 3-5% error of margin. Apple will not do anything unless the battery is under 80% design capacity. So just use it and enjoy it.
Wear is NOT linear - as my 6s+ started with 96% and it hasn't changed much.
Best thing I ever did to enjoy my phone? Turn off battery % and just use it.