The increased variability of interest rates experienced during the early 1980s led many commercial banks to shift the interest rate they charge on farm loans from a fixed to a variable rate (Zook and LaDue). Although the Farm Credit System had used variable rates for a number of years, the index for their rate was the average cost of funds, which is less volatile than some of the rate indices used by commercial banks. Further, in contrast to the situation when the Farm Credit Service switched to variable rates, the shift of commercial banks to variable rates left most farmers with no fixed rate general credit source, no matter how important a fixed debt service commitment might be to their business.