I think, there will be good idea, if coinmarketcap.com for each currency will print Share ratio on currency-specific page.
Details about Sharpe ratio: https://en.wikipedia.org/wiki/Sharpe_ratio

This is useful and important value for professional investors.

For compute, you can assume simplified formula with Rb=0. This is widely used practical approach.

We propose to print annual and monthly Share on the currency detail page.
Please note - monthly sharpe need multiply to 12, for adjust value to annual and make it comparable.