A railroad intends to purchases 12 million gallons of diesel fuel in one month and seeks to hedge the price risk in the nearby heating oil futures contract traded on NYMEX. The heating oil futures contract is written on 42,000 gallons of heating oil. The railroad will tail the hedge to allow for the impact of marking-to-market. Spot diesel fuel is trading at $2.048 per gallon and the nearby heating oil futures contract is trading at $2.034 per gallon. The standard deviation of monthly price changes is 2.51% for spot diesel fuel and 2.99% for the heating oil futures contract. If the railroad establishes a hedge position of 217 in the nearby heating oil contract, what is the implied correlation (to three decimal places) between monthly price changes of spot diesel and heating oil futures?