The Ravens beat the Pittsburgh Steelers 31-7 for the second time this season. and improved to a 12-3 record, moving up to the #2 AFC playoff seed with a Colts loss during Week 16 against the Texans. The Ravens defense held Pittsburgh RB Willie Parker to just thirty yards rushing and sacked Ben Roethlisberger five times. On offense Steve McNair threw three TD passes and was 21/31 for 256 yards with 2 interceptions. RB Jamal Lewis added 77 yards and a touchdown, and Matt Stover delivered a 26-yd field goal. This was the Ravens first win at Heinz Field since 2001. It was also the first time the Baltimore Ravens swept the season series against the Steelers in franchise history. The Ravens also tied their franchise record for wins in a season at 12 while improving to 12-3. They had last won 12 games during the 2000 season, after which they went on to win Super Bowl XXXV in Tampa.
Question: How many yards were added by the Pittsburgh RB?
Answer: 77