The stock-to-flow indicator is a popular indicator of the price of a cryptocurrency, typically with a limited supply. The model looks at each cryptocurrency as a fixed, scarce resource similar to precious metals or stones. Because there is a known limited supply without new sources to be found, investors use these assets as a store of value.

We calculate the indicator by taking the total circulating global supply and dividing it by the amount produced per year. In Bitcoin, you can do this with easily found circulation figures and data on newly mined coins. Decreasing returns from mining leads to a higher ratio reflecting its scarcity, making the asset more valuable. As Bitcoin goes through a reward halving event periodically, we can see this reflected in the flow of new coins into the market.

As you can see, stock-to-flow has been a reasonably good indicator of the price of Bitcoin. Bitcoin’s price has been superimposed on the 365 day average of the ratio and shows a good match. The model does have some drawbacks, however. 

For example, gold currently has a stock-to-flow ratio of around 60, meaning it would take 60 years to mine the current supply of gold at the current flow. Bitcoin will roughly be on track to have a ratio of 1600 in around 20 years, setting price predictions and a market cap higher than the world’s current wealth. 

Stock-to-flow models also struggle when deflation happens, as this would suggest a minus price. As people lose the keys to their wallets and no more bitcoins are produced, we would see a negative ratio. We would see the stock-to-flow ratio flow go towards infinity and then become minus if we displayed this graphically.