Are lumber prices really at their lowest level ever? It may seem so, but inflation can make past years' prices tough to compare. So Richard Heath, an accountant and dealer consultant based in Surfside Beach, S.C., took price data as recorded by an eastern North Carolina dealer, then adjusted the numbers to reflect changes in the producer price index. The graph at left shows weekly prices for half-inch plywood in 2009 and three previous years. The graph at right shows those past years' prices in 2009 dollars. The result? Plywood prices were relatively low last year, but they weren't always the cheapest.