the earning depends on many factors , and I agree with many others the factors are vague. But in my case, for some reason, things seem to be working in my favor: I earn around 3 tokens per day.
My relay has been up since the end of March. The Observed Bandwidth is most of the time at 8 MB/s, and the relay has the flags: FAST, RUN, V2Dir.
Whenever my earnings fluctuate ( dropping to 2 tokens per day), the only noticeable change is a drop in the Observed Bandwidth. Once it increases again, so do the earnings.
According to their Discord channel, Observed Bandwidth is measured based on upload speed only
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