You would need to add your complete, all-time cryptocurrency transaction history to CoinTracker. This ensures that they have all of the data needed to correctly calculate cost basis and proceeds for each transaction.
Entering all exchanges, self-custody wallets, coins/tokens, ICOs, trades, DeFi transactions, transfers, withdrawals, and deposits allow them to reference all assets in their calculations. Leaving any transactions out, whether from previous years or because you believe they may not be relevant will skew your portfolio and will cause your tax calculations to be incorrect.
If errors do occur on some of the CoinTracker transactions, then you would have to edit the cost basis and/or proceeds. If you do not have a record of your cost basis on these transactions, then you would need to put zero.
