Many years ago, falling prices were a sign of improved efficiency and expanding wealth, and of widening consumer choice. Thanks to the spread of electricity and other such wonders in the final quarter of the 19th century, prices dwindled year by year at a rate of 1.5% to 2% per year. People didn't call it deflation – they called it progress. Similarly, in the 1920's there were advances in production techniques. The prices didn't decline and didn't rise. They were stable. Looking back on the 20's from the vantage point of the 30's, many people wondered why prices had not fallen. They concluded that it was because the central banks were emitting too much credit, and that credit had served to inflate asset values. It had also pushed the world into a very imbalanced credit and monetary situation towards the close of the 20's.