added next halving date

Author: 8go

README.md

@@ -17,31 +17,36 @@ If desired rename `s2f.py` to `s2f`. Just type `s2f.py` into your terminal. Try
 Example output of `s2f.py`:
 
 ```
-Data sources:                 messari.io and coinmetrics.io
-Calculated for date:          2020-06-15
-Circulating BTC:              18,411,899 BTC
-Annual inflation:             1.83 %
-Forward stock-to-flow ratio:  54.75
-Forward stock-to-flow price:  98,163 USD
-463-day Stock-to-flow ratio:  27.03
-463-day Stock-to-flow price:  9,556 USD
+Data sources:                     messari.io and coinmetrics.io
+Calculated for date:              2021-05-26
+Circulating BTC:                  18,725,305 BTC
+Annual inflation:                 1.80 %
+Estimated next halving date:      06 May 2024
+Forward stock-to-flow ratio:      55.70
+Forward stock-to-flow price:      103,867 USD
+463-day Stock-to-flow ratio:      46.68
+463-day Stock-to-flow price:      57,979 USD
+Current price:                    39,322 USD
+Deviation of 463-day S2F price:   32.18 %
 ```
 
 Example output of `s2f.py --verbose`:
 
 ```
-This program prints the Bitcoin Stock-to-Flow ratio and price.
-Read about Stock-to-Flow here:    https://medium.com/@100trillionUSD/efficient-market-hypothesis-and-bitcoin-stock-to-flow-model-db17f40e6107
+Read about Stock-to-Flow here:    https://medium.com/@100trillionUSD/fficient-market-hypothesis-and-bitcoin-stock-to-flow-model-db17f40e6107
 Compare with Stock-to-Flow data:  https://bitcoin.clarkmoody.com/dashboard/
 Compare with Stock-to-Flow graph: https://digitalik.net/btc/
-Data sources:                 messari.io and coinmetrics.io
-Calculated for date:          2020-06-15
-Circulating BTC:              18,411,899 BTC
-Annual inflation:             1.83 %
-Forward stock-to-flow ratio:  54.75
-Forward stock-to-flow price:  98,163 USD
-463-day Stock-to-flow ratio:  27.03
-463-day Stock-to-flow price:  9,556 USD
+Data sources:                     messari.io and coinmetrics.io
+Calculated for date:              2021-05-26
+Circulating BTC:                  18,725,305 BTC
+Annual inflation:                 1.80 %
+Estimated next halving date:      06 May 2024
+Forward stock-to-flow ratio:      55.70
+Forward stock-to-flow price:      103,867 USD
+463-day Stock-to-flow ratio:      46.68
+463-day Stock-to-flow price:      57,979 USD
+Current price:                    39,155 USD
+Deviation of 463-day S2F price:   32.47 %
 ```
 
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