On rural, 2-lane, low-volume, on-system roads
County average (8 years) = 0.45 crashes/MVMT
Note: Crash rate is expressed in terms of the diameter of the ball. The three balls on the lower left corner indicates 1.0, 0.5, and 0.25 crashes per MVMT, respectively. Low-volume roads refer to road segments carrying fewer than 2,000 vehicles per day.