Am I improving at the average rate per year?

I started playing and learning chess when I was 15, I did not attend any lessons. My estimated FIDE using an online engine is 1500-1600. Am I improving at an average? 

There's not enough information for me to tell... I guess you're tracking your rating?

You haven't given any information about your rate of improvement.

FWIW the normal rate of improvement for an adult is not much above zero if at all (if you work very hard at improving as an adult of course you still can- see Milliern for a great example- just most don't put in the effort, since it's harder and time-consuming). The normal rate of improvement for a kid is probably at least one hundred points per year, and that's pretty conservative.

I seem to be stuck in the 800s