Coin Days Accumulated

Running total of all coin-days ever created minus all coin-days ever destroyed — the total stored economic energy in the network

Property	Value
Category	Coin Days
Unit	coin-days
Resolution	1d
Assets	BTC
Tier	Basic
API Endpoint	GET /v1/coindays
Field	coindays_accumulated

Overview

Coin Days Accumulated (CDA) is the running cumulative sum of Net Coin Days from the genesis block to the present day. It represents the total stock of dormancy energy stored across all unspent Bitcoin — the aggregate age-weighted holding of the entire UTXO set.

CDA grows when the network is accumulating (most days) and shrinks on days of massive old-coin spending. Over Bitcoin's history, CDA has grown roughly monotonically, punctuated by brief drawdowns during extreme market events.

Formula

$$\text{CDA}_T = \sum_{t=0}^{T} \text{Net Coin Days}_t = \sum_{t=0}^{T} \left( S_t - \text{CDD}_t \right)$$

Where:

• $T$ is the current date
• $S_t$ is the circulating supply on day $t$ (= Coin Days Created)
• $\text{CDD}_t$ is coin-days destroyed on day $t$
• The sum starts from the genesis block (January 3, 2009)

Interpretation

• Rising CDA (normal state): The network is accumulating dormancy faster than spending it — coins are aging, HODLers are holding
• CDA plateau or dip: Significant old-coin spending is consuming accumulated dormancy at a rate matching or exceeding creation — distribution phase
• CDA growth rate: The slope of CDA reflects the network's savings rate — how quickly the collective holder base is building long-term positions
• Scale context: CDA is measured in billions of coin-days and grows with both supply issuance and holder behavior

Use Cases

• Long-term accumulation trend visualization: CDA provides a single curve showing the macro trend of Bitcoin holder conviction over its entire history
• Foundation for Liveliness and Vaultedness: Liveliness = CDD / CDA (activity relative to dormancy), Vaultedness = 1 − Liveliness — both are direct derivatives
• Cycle regime classification: Accelerating CDA growth = accumulation regime; decelerating = distribution regime
• Cross-cycle comparison: CDA normalized by supply or market cap enables comparison of holder behavior across different market cycles

API Usage

curl -H "Authorization: Bearer YOUR_API_KEY" \
  "https://api.blocklens.co/v1/coindays?start_date=2024-01-01&end_date=2024-12-31&limit=365"

Related Metrics

• Coin Days Destroyed — Sum of coin age × amount for all spent UTXOs per day — a fundamental measure of on-chain economic activity
• Net Coin Days — Coin Days Created minus Coin Days Destroyed — positive means the network is aging (accumulating), negative means old coins are moving
• Circulating Supply — Total BTC ever mined