American Express allows you to download transaction data in CSV format. Information from a credit card account comes with the following columns:

Date, Reference Number, Amount, Payee, Additional notes

For our purposes, all we need is the date, the amount, and the payee (which will be the memo). We want to end up with this new format:

Date, Memo, Amount

Since AMEX doesn't provide the running balance, we can just use all zeros and have PBooks calculate it after the import.

Another oddity with the American Express export is that they have the inverse of the real "accounting amount", meaning that if you purchase a television for $400, it shows up as -$400. The entry amounts actually have to be multiplied by -1 prior to import.