The level of real net farm income fell to Great Depression levels in 1983 when surpluses of specific crops grew in the early 1980s (see Figure 18.6,A). Farm revenue was suppressed by declining export demand for U.S. crops due to a rising value of the U.S. dollar Rising interest rates also increased farm production expenses. Interest payments on farm debt outstanding rose to 19% of cash production expenses in the 1980s, as opposed to 7% in the 1970s (see Figure 18.6,B). These trends put downward pressure on real net farm income and farm land prices (see Figure 18.6,D).