The slowing economy combined with high petroleum prices is expected to constrain growth in U.S. consumption of liquid fuels and other petroleum products to just 40,000 barrels per day (bbl/d) in 2008.  After accounting for increased ethanol use, U.S. petroleum consumption falls by 90,000 bbl/d.   U.S. real gross domestic product is expected to decline slightly in the first half of the year and then start growing again, with growth for 2008 as a whole at 1.3 percent, the slowest annual rate since 2001.