5. Money interest rates throughout the world have generally been higher since World War II than in the prewar period. Indicate which of the following might provide part of the explanation and analyze: Higher rates of time-preference (changes in tastes). Higher rates of time-productivity (changes in investment opportunities). Lower ratios of current to anticipated future incomes (increased relative scarcity of current endowments). Higher rates of inflation (changes in anticipations as to monetary policies of gov- ernments).