This uses transaction data from your wallet. Anything that doesn't show up in your wallet transaction list wont be captured by this tool. I suggest looking at Chia Tracker for a more complete look at your transaction history.
If your chia root is not the default, make sure its set in your env before running:
export CHIA_ROOT=<path to chia root>Then, just run go run main.go and it will generate transactions.csv file for wallet ID 1