Have you ever wondered why BTC is halved (approximately) every four years? You know, if the output is reduced by 16% every year, 0.84^4 is about 0.5. Why not gradually reduce the output every year? If the output is gradually reduced every four years, the cost and output curves of BTC will be smoother. A large halving every four years is actually a bit jumpy. In fact, the Bitcoin code is designed to halve every 210,000 blocks. However, Satoshi Nakamoto's design controls the difficulty and generally produces one block every 10 minutes. Strictly according to the mining of one block every 10 minutes, the time for 210,000 blocks is 210000*10/60/24=1458 days and 8 hours. The difference of 2 days and 12 hours is 4 years. The first BTC block was generated at around 6:15 pm Greenwich time on January 3, 2009. Not on the 1st, not on the 2nd, not at any other time. If it is strictly one block every 10 minutes, the first halving will happen on December 31, 2012. If there were no miners rushing to mine, the next BTC halving would have been in December of 2016, 2020, 2024, etc. This happens to be the month after the US election. In fact, the original intention of Satoshi Nakamoto to design Bitcoin, the so-called decentralization, was only aimed at the US dollar. Fortunately, Bitcoin has lived up to its mission and has always been inversely linked to the US dollar index.