Well crap, now I've noticed another problem because of your diligence with the math. I've really got to stop being so lazy not extrapolating out those numbers. It looks like 21 million tokens will be issued by year 40 based on your table. According to https://en.bitcoin.it/wiki/Controlled_supply, Bitcoin's yearly emission rate is 2625000, but when I do the math of 50 tokens every 10 minutes, I get the 2628000. I'm not sure where the difference is coming from.