As in their previous match this year, the Ravens scored first with an 18-yard field goal by kicker Billy Cundiff, the only points scored in the first quarter by either team.  Steelers kicker Shaun Suisham answered with a 36-yard field goal early in the second quarter, and a 30-yard field goal near the end, but both of these were quickly matched by Baltimore's Cundiff with a 43-yard and 51-yard field goal, respectively, giving Baltimore a 9-6 lead at halftime.  The Ravens then increased their lead in the third quarter when Ray Rice scored the first touchdown of the game on a 4-yard run.  The Steelers rallied in the fourth quarter, with running back Rashard Mendenhall making a 1-yard run to score a touchdown, and then taking the lead for the first time in the game when quarterback Ben Roethlisberger hit  Mike Wallace in the endzone with a 25-yard pass for a second touchdown. In the game's final minutes the Ravens began a 92-yard drive, culminating in a 26-yard touchdown pass by quarterback Joe Flacco to wide receiver Torrey Smith leaving 8 seconds on the clock improving the Ravens record to 6-2.
Question: How many yards was the shortest field goal?
Answer: 18