The chart shows how many 比特币现金 Coin-Days were destroyed by transacting BCH. The Coin-days destroyed (CDD) is an alternative measure to the total transaction volume, since it accounts for the 'age' of each coin. When an older coin is transacted, the coin's CDD will be bigger than of the younger coin. The CDD measure includes a new dimension, the age of coins into the account of the overall economic acitivity