Patent ID: 8165941

Claim:
A computer-implemented method comprising: retrieving a plurality of computer-executable instructions from computer-readable storage; and executing the computer-executable instructions on at least one computer processor, thereby causing computer hardware to perform operations comprising: associating each of a plurality of financial accounts with a financial account card, each account having a payment plan and integrating both credit transactions and savings transactions into a single account balance with different effective interest rates; defining account payment plans that each have a fixed amortization rate, a fixed or adjustable nominal interest rate, a payment cycle, an account unit value, an adjustment index of value and an indicator of whether or not the nominal interest rate is proportionally applied in a first cycle between a transaction date and a deadline of the cycle; and initiating an entry of a nominal value as a credit transaction in a first cardholder account and as a savings transaction in a second cardholder account, wherein the first cardholder account and the second cardholder account share a same payment plan and are issued by a same financial institution, wherein the entry is facilitated by a computer, wherein a credit transaction creates or increases a debt balance, changes a savings balance to a debt balance, or diminishes or liquidates a savings balance, wherein a savings transaction creates or increases a savings balance, changes a debt balance to a savings balance, or diminishes or liquidates a debt balance, and wherein the first cardholder account corresponds to a buyer and the second cardholder account corresponds to a seller of at least one of a good, a service, money, or a security that has an effective value, wherein the nominal value of the savings transaction and the credit transaction is financially equivalent to the effective value, considering parameters of the payment plan and a current effective market interest rate or an effective interest rate accepted by a holder of the financial account card.