Anyone who studies the past soon comes up against the question of what the money amounts mentioned really meant. There are a number of sites that will "tell" us, but translating 200-year-old dollar values into today's economy is a very difficult and dubious task. I proposed some alternatives in a blog post last year and recommended the site Measuring Worth if you're determined to try to make such a statement.
But for several reasons it seemed more reasonable to compare apples to apples and describe purchases from back then that we might be able to grasp in in-kind terms today.
So when I wanted to know what it meant for a War of 1812 soldier to be paid about $12 for a couple months' service (two separate hitches), I went looking. I found that that in 1812 in near-frontier Cincinnati that amount of money would have bought
"more than 250 pounds of beef.1 In Jefferson County [New York] some 20 years later it would have bought about 100 pounds of maple sugar.2"1 Thomas Senior Berry, Western Prices Before 1861: A Study of the Cincinnati Market (Cambridge: Harvard University Press, 1943), Table 23, “Median Annual Prices of Fourteen Leading Commodities in the Ohio Valley, 1786-1817,” pp. 568-69; digital images, Food Timeline (http://www.foodtimelines.org/prices1786-1817.pdf : accessed 9 April 2013).
2 Henry H. Lyman, “Sugar-Making,” in Memories of the Old Homestead: A Story about Lorraine, NY (1900; reprint, Historical Association of South Jefferson, 1999), 23rd paragraph; digital image, Adams, New York History and Genealogy (http://www.adamsny.net/lyman.html : accessed 9 April 2013).
Harold Henderson, "What was $12 worth in 1814?," Midwestern Microhistory: A Genealogy Blog, posted 22 May 2013 (http://midwesternmicrohistory.blogspot.com : accessed [access date]). [Please feel free to link to the specific post if you prefer.]