Fisher believed that investors and savers – people in general – were afflicted in varying degrees by "money illusion"; they could not see past the money to the goods the money could buy. In an ideal world, changes in the price level would have no effect on production or employment. In the actual world with money illusion, inflation (and deflation) did serious harm. For more than forty years, Fisher elaborated his vision of the damaging "dance of the dollar" and devised various schemes to "stabilize" money, i.e. to stabilize the price level. He was one of the first to subject macroeconomic data, including the money stock, interest rates, and the price level, to statistical analyses and tests. In the 1920s, he introduced the technique later called distributed lags. In 1973, the "Journal of Political Economy" posthumously reprinted his 1926 paper on the statistical relation between unemployment and inflation, retitling it as "I discovered the Phillips curve". Index numbers played an important role in his monetary theory, and his book "The Making of Index Numbers" has remained influential down to the present day.