The Monero block reward = (M - A) * 2-20 * 10-12, where A = current circulation.
Approximately 86% of pre-tail Monero will be mined within 4 years of its launch. What was the stated rational of the original developer(s) for selecting this particular emission curve? Where faster or slower emission curves considered for Monero after the community takeover from thankful-for-today? Was a change considered at the same time the tail emission was added?
It was chosen arbitrarily by thankful_for_today, with no research or thinking of any kind. But we're stuck with it, and since it's part of the social contract it isn't going to change:)
The emission curve is the same as Bytecoin's except stretched out by a factor of 2. There was an extended debate about slowing the emission curve at some point that seems to have concluded around the end of 2014:
https://bitcointalk.org/index.php?topic=753252.msg9842542#msg9842542
It's hard to google up since it's for the most part buried in bitcointalk threads, but I think there was some MEW group (Monero Economy Workgroup?) that brought the issue up for debate, but ultimately it was rejected.
