Bitcoin has just experienced a once-in-four-years event: its third halving, which has cut the miner block reward from 12.5 BTC to 6.25 BTC.
Source: https://cointelegraph.com/news/it-happened-bitcoin-just-experienced-third-halving-in-its-history
It Happened: Bitcoin Just Experienced Third Halving in Its History
May 11, 2020
CoinTelegraph