The three price indices for the three different periods are color-coded as before. Here we see that in peacetime, before 1940, the price level was quite unstable from one period to the next but was about as likely to fall as to rise. Since 1950, however, it seems to be much more stable, but more likely to show positive inflation rather than declining prices. However, we should be a little careful in interpreting this. The price index used for the earlier period is less exact, and some of its instability might reflect that, rather than real differences in the stability of the price level.
Causes of Inflation 
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