[Term] Fully Indexed Rate [Definition] 
The price of the ARM is calculated by adding Index + Margin = Fully Indexed Rate. This is the interest rate your loan would be at without a Start Rate (the introductory special rate for the initial fixed period). This means the loan would be higher if adjusting, typically, 1–3% higher than the fixed rate. Calculating this is important for ARM buyers, since it helps predict the future interest rate of the loan.