We can compare the yearly rate of a cohorts balance change to the volume of BTC mined over the same period. This provides a relative measure of the amount of new Issuance which was theoretically absorbed by this cohort. Note that values over 100% are possible as coins can be transferred from other investor cohorts (e.g. Whales to Shrimps, or Exchanges to Fish).
Values over 100% indicate that the cohort increased their aggregate balance by more than all coins mined in the past year, and thus acted as a net absorbing balance.
Values near 0% indicate that the cohorts aggregate balance was approximately flat over the last year.
Values below 0% indicate that the cohort aggregate balance decreased over the past year, and was distributed alongside newly issued coins.
Further References
For more information, please see our research report where this metric was first featured: The Shrimp Supply Sink: Revisiting the Distribution of Bitcoin Supply.