1989 18.000607 0.055554 This indicates that the item costing $1 in 1900 would cost approximately $18 in 1989. The second column is the inverse function, meaning an item costing $1 in 1989 would have cost about $.05 or $.06 back in the year 1900. You should be able to find some interesting trends such as that prices were falling back in 1875 as industrial growth swept the United States and the West was being developed. [Based on an item costing $67 in 1875 {$1,000 in 1989}] Prices fell from $67 to $47 from 1875 to 1898, in a rather steady progression, and then rather steadily rose back for the next two decades until World War I, until they reached $67 again in 1913 and $69 in 1914, which were the last two years of moderate inflation until after 1919, when pricing dropped from a high of $139 after doubling since 1914. Prices stabilized during the rest of the 1920's about $110 until 1930, and the Great Depression, in which prices fell to $88 in 1933 and then back to the ranges of the 1920's-- until around the end of World War II, when prices went out of control, rising from an average of around $120 for WWII on the whole to $200 in 1951. It took 17 years to hit the $300 level in 1968 and 22 years to double to $400 in 1973. From 1973 it took only 9 years to double again to $800 for the year 1982. [At 7% per year, it takes 10 years for inflation to cut $1 to $.05, at 1% it takes 70 years, at 3% it is 23 years and at 4% it takes about 18 years]. Based on 4% inflation, it will be 1990 1.040000 [based on 1989 as 1.000000 base year] 1991 1.081600 [and based on 4.0000% inflation rate] 1992 1.124864 1993 1.169856 which would be an 11 year span for prices to double, since they were at 0.793652 in 1982 to 1.169856, projected 1993] Below are files for every year on this chart independently listed with that year as the base year, so you can look up for instance, what something from 1930 would have cost in 1950, or the reverse. YEAR: 2010