Percent Change in Number of Motorcycle Fatalities and Fatality Rates Two Years Before and After Law Change, bar chart, date represented in table below:

Annual Rate of Motorcycle Fatalities per 10,000 Motorcycles Registered, Source: FARS (1998-2002), line chart, x-axis - 1998-2002, increments of 1 year, y-axis - 0-8, increments of 1, Fatalities per 10,000 motorcycles registered, data - "helmeted, unhelmeted, helmet unknown"