If Bitcoin delivered 50 coins every 10 minutes (600 seconds) the first year, then it should have delivered 50 x (1577000/10) = 7885000 Bitcoin the first year.

But I cannot see this number in any charts like in this one for example where it is said that the first years were added 2625000 bitcoins.

https://en.bitcoin.it/wiki/Controlled_supplySo what is the exact formulas to determine how many bitcoins are issued / year (before halfing)

To calculate theoretically how many bitcoins are mined in one year (assuming 50 BTC per block):

min/year = 365.25 days/year * 24 hr/day * 60 min/hr = 525960 min/year

blocks/year (average) = (525960 min/year) / (10 min/block) = 52596 blocks/year

bitcoin/year (1 full year, 50 BTC per block) = 52596 blocks * 50BTC/block = 2629800 BTC/year

Note: This is assuming 10 minutes per block, which is just an average. Also, the first block was mined on Jan 3, 2009 and did not continue every 10 minutes at the beginning, it took a couple weeks to begin to stabilize around 10 minutes:

https://i.stack.imgur.com/Ogxtj.pngMaybe someone can comment as to why the wiki has 2625000 BTC as the estimate per year, I'm not sure why.

However, The estimation for a blocks in a year in Bitcoin is 210000/4, where 210000 is the subsidy halving height (just short of 4 years). At 50 BTC per block this is 2625000.

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