Solana's price has spiked recently, more than doubled since Jan 1st, 2021. The market cap has grown even more significantly, from $81 million on Jan 1st to over $1 billion as of today, due to a big jump in circulating supply from Jan 5 to Jan 6, according Coinmarketcap.
Metcalfe's law states that the effect of a telecommunications network is proportional to the square of the number of connected users of the system (n^2).
If Metcalfe's law holds true for cryptocurrency between price and user base, we'll expect the user base (holders) of Solana to increase, too. It's hard to track the DAU (daily active user) on any particular chain, but it'd be nice to see how many token holders on any particular day. These are something the APIS project may be able to solve.
To learn more about how you can build on top of any blockchain using the APIS project, please check out the developer site, or PM me on Twitter
How about tracking daily on-chain transaction numbers as a metric for daily usage?