DOT HS August Time of Day and Demographic Perspective Of Fatal Alcohol-Impaired-Driving Crashes. Time of Day

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1 TRAFFIC SAFETY FACTS Research Note DOT HS August 2011 Time of Day and Demographic Perspective Of Fatal Alcohol-Impaired-Driving Crashes Alcohol-impaired driving continues to be one of the major problems on our Nation s highways. Drivers are considered to be alcohol-impaired when their blood alcohol concentration (BAC) is.08 grams per deciliter (g/dl) or higher. Thus, any crash involving a driver with a BAC of.08 or higher is considered to be an alcoholimpaired-driving crash, and fatalities occurring in those crashes are considered to be alcohol-impaired-driving fatalities. This research note reviews characteristics of fatal alcohol-impaired-driving crashes using data from the Fatality Analysis Reporting System (FARS). The number of overall motor vehicle crash fatalities has decreased over the past several years. From 2008 to 2009, there was a 9.7 percent decrease in fatalities, from 37,423 to 33,808. In the same year, alcohol-impaired-driving fatalities decreased from 11,711 to 10,839, a decrease of 7.4 percent. The percentage of motor vehicle crash fatalities that are alcohol-impaired driving related, however, has changed little over the years. In 2008, it was 31 percent of all fatalities, and 32 percent in Time of Day Overall, about one-third of all fatal crashes involve alcohol-impaired drivers. However, during certain hours of the day, these crashes occur more frequently (see Table 1). In 2009, from midnight to 3 a.m., two-thirds of fatal crashes involved an alcohol-impaired driver twice the overall average. Two-thirds of all motor vehicle fatalities between the hours of midnight and 3 a.m. occurred in alcohol-impaired-driving crashes, and more than half (55%) of drivers involved in fatal crashes at those hours, were alcohol-impaired. Other times of day with especially high percentages of alcoholimpaired-driving were 6 p.m. to midnight, and 3 a.m. to 6 a.m. The numbers and percents across fatal crashes, fatalities, and drivers involved are relatively consistent. Table 1 Fatal Crashes, Fatalities and Drivers Involved in Alcohol-Impaired-Driving (AID) Crashes by Time of Day, 2009 Time of Day Fatal Crashes Fatalities Drivers Involved Total AID % AID Total AID % AID Total AID % AID 9 a.m. to Noon 2, % 3, % 4, % Noon to 3 p.m. 3, % 4, % 6, % 3 p.m. to 6 p.m. 4, % 5,468 1,047 19% 7, % 6 p.m. to 9 p.m. 4,988 1,629 33% 5,420 1,786 33% 7,229 1,672 23% 9 p.m. to Midnight 4,359 2,024 46% 4,767 2,227 47% 5,849 2,088 36% Midnight to 3 a.m. 3,957 2,599 66% 4,378 2,896 66% 4,920 2,706 55% 3 a.m. to 6 a.m. 2,587 1,345 52% 2,824 1,487 53% 3,315 1,388 42% 6 a.m. to 9 a.m. 2, % 3, % 4, % Total* 30,797 9,813 32% 33,808 10,839 32% 45,230 10,102 22% Source: FARS 2009 Annual Report File (ARF) *Total includes fatalities during unknown time of day.

2 2 Overall, an average of one alcohol-impaired-driving fatality occurred every 48 minutes in However, these fatalities did not occur evenly throughout the day. Table 2 shows, for each three-hour increment of the day, the total number of traffic fatalities, the number of alcohol-impaired-driving fatalities, and the percentage of fatalities that were in alcohol-impaired crashes. Table 2 also shows the average number of total and alcohol-impaired-driving traffic fatalities per hour for each timeframe. During midnight to 3 a.m., there was an average of four fatalities per hour, with three of those occurring in alcohol-impaired-driving crashes. From 3 p.m. to 6 p.m., on the other hand, there were more traffic fatalities an average of five per hour but only one involved in an alcohol-impaired-driving crash. Table 2 also shows that, from midnight to 3 a.m., there was an average of one traffic fatality every 15 minutes, while from 3 p.m. to 6 p.m. there was an average of one every 12 minutes. This result was simply due to a larger number of fatalities during the latter time frame. Looking only at alcohol-impaired-driving fatalities, however, there was an average of one every 23 minutes (nearly 3 per hour) from midnight to 3 a.m., compared to one every 63 minutes (less than 1 per hour) from 3 p.m. to 6 p.m. The percentage of alcohol-impaired drivers involved in fatal crashes by time of day also remains consistent from year to year. Figure 1 shows the percentage of alcohol-impaired drivers by time of day within 3-hour groupings. Midnight to 3 a.m. has, by far, the highest percentage of alcohol-impaired drivers involved in fatal crashes, more than 10 percentage points higher than the next highest time frame. Recall for comparison that overall, 22 percent of drivers involved in fatal crashes were alcohol-impaired. Since the primary interest is on impaired driving, the remainder of this research note will focus primarily on the drivers involved. Figure 1 Percentage of Impaired Drivers Involved in Fatal Motor Vehicle Traffic Crashes by Time of Day, % 50% 40% 30% 20% 10% 0% 5% 9 a.m. to Noon 7% 12% Noon to 3 p.m. Source: FARS 2009 (ARF) 23% 3 p.m. to 6 p.m. 36% 6 p.m. to 9 p.m. 55% 9 p.m. to Midnight 42% Midnight to 3 a.m. 10% 3 a.m. to 6 a.m. 6 a.m. to 9 a.m. Table 3 exhibits this information for the last 10 years. The same data is shown graphically in Figure 2, illustrating the hours most likely to involve alcohol-impaired driving, as well as the consistency from year to year. While the number of fatalities in alcohol-impaired- driving crashes decreased by nearly 20 percent over these 10 years, from 13,324 in 2000 to 10,839 in 2009, the percentages by time of day changed very little. Table 2 Average Fatalities per Hour in Fatal and AID Fatal Motor Vehicle Traffic Crashes, by Time of Day in 3-Hour Periods, 2009 Time of Day Fatalities **Fatalities/Hour **One Fatality Every Minutes Total AID % AID Total AID Total AID 9 a.m. to noon 3, % 3 < Noon to 3 p.m. 4, % 4 < p.m. to 6 p.m. 5,468 1,047 19% p.m. to 9 p.m. 5,420 1,786 33% p.m. to midnight 4,767 2,227 47% Midnight to 3 a.m. 4,378 2,896 66% a.m. to 6 a.m. 2,824 1,487 53% a.m. to 9 a.m. 3, % 3 < Total* 33,808 10,839 32% Source: FARS 2009 (ARF) *Total includes fatalities during unknown time of day. **Fatalities per hour and by number of minutes have been rounded to the nearest whole number.

3 3 Table 3 Percentage of Alcohol-Impaired Drivers (BAC.08+) Involved in Fatal Motor Vehicle Traffic Crashes, by Year and Time of Day Time of Day a.m. to noon 5% 5% 5% 5% 5% 5% 6% 5% 5% 5% Noon to 3 p.m. 7% 7% 7% 6% 6% 7% 7% 7% 6% 7% 3 p.m. to 6 p.m. 12% 12% 12% 11% 11% 12% 12% 11% 12% 12% 6 p.m. to 9 p.m. 24% 24% 23% 23% 22% 23% 23% 22% 22% 23% 9 p.m. to midnight 37% 35% 35% 35% 34% 35% 35% 34% 35% 36% Midnight to 3 a.m. 54% 54% 53% 54% 53% 53% 52% 54% 54% 55% 3 a.m. to 6 a.m. 39% 42% 41% 38% 40% 38% 40% 40% 38% 42% 6 a.m. to 9 a.m. 8% 8% 8% 7% 8% 8% 8% 9% 9% 10% Unknown 58% 54% 57% 51% 52% 52% 50% 51% 45% 43% Total 21% 21% 21% 21% 21% 21% 22% 22% 22% 22% Source: FARS 2000 to 2008 (Final) and 2009 (ARF) Figure 2 Percentage of Alcohol-Impaired Drivers in Fatal Crashes, By Time of Day, % 50% 40% 30% 20% 10% 0% Midnight to 3 a.m. 9 a.m. to Noon 6 p.m. to 9 p.m. Source: FARS 2009 (ARF) a.m. to 6 a.m. Noon to 3 p.m. 9 p.m. to Midnight a.m. to 9 a.m. 3 p.m. to 6 p.m. Weekends and nighttime present much higher percentages of alcohol-impaired drivers involved in fatal crashes than do weekdays. The rate of alcohol-impaired drivers involved in fatal crashes in 2009 was four times higher at nighttime (37%), defined as 6 p.m. to 5:59 a.m., than during the day (9%) in Drivers involved in fatal crashes were twice as likely to be alcohol-impaired on weekends (31%), defined as Friday 6 p.m. to Monday 5:59 a.m., than during the week (16%). Driver Demographics Fatal crash data has consistently shown that drivers 21 to 24 years old have the highest level of involvement in alcohol-impaired fatal crashes, compared to drivers of other age groups (see Table 4). In 2009, more than onethird (35%) of 21- to 24-year-old drivers involved in fatal crashes were alcohol-impaired. In contrast, less than one-fourth (22%) of the total drivers involved in fatal crashes were alcohol-impaired (Table 1). While drivers 21 to 24 constituted 10 percent of all drivers involved Table 4 Percentage of Alcohol-Impaired Drivers (BAC.08+) Involved in Fatal Motor Vehicle Traffic Crashes, by Age Group and Year Year % 33% 30% 27% 24% 19% 13% 7% 4% % 33% 30% 28% 25% 19% 13% 8% 5% % 34% 30% 27% 25% 20% 12% 7% 4% % 34% 32% 28% 25% 20% 12% 6% 4% % 35% 33% 29% 26% 22% 13% 7% 3% Source: FARS 2005 to 2008 (Final) and 2009 (ARF)

4 4 in fatal crashes in 2009, they constituted 16 percent of all alcohol-impaired drivers involved in fatal crashes, making them the most over-involved age group for alcohol-impaired drivers. Although minimum-age drinking laws exist in all 50 States, the District of Columbia, and Puerto Rico, nearly 20 percent of drivers in the under-21 age group involved in fatal crashes had BACs of.08 or more. Table 5 looks at the data subdivided by gender. Note that across age groups, male drivers involved in fatal crashes were far more likely to have been alcoholimpaired than were female drivers. In addition, this pattern shows very little variation across the years. Motorcycle riders had the highest rate of alcohol impairment (29% in 2009) among drivers of all vehicle types. Large-truck drivers (2%) had by far the lowest rates of alcohol impairment. From 2000 to 2009, the percent of alcohol-impaired passenger vehicle (passenger cars, pickups, vans and Sport Utility Vehicles [SUVs]) drivers involved in fatal crashes was about 23%, and remained virtually unchanged among each of the vehicle types. Pickup truck drivers continued to have the highest percentage (27% in 2009) of alcohol impairment compared to other passenger vehicle drivers. Passenger car and SUV drivers each had a rate of 23 percent alcohol impairment in fatal crashes in The percentage of alcohol-impaired van drivers (12%) involved in fatal crashes continued to be substantially lower than that of other passenger vehicle drivers. Regardless of time of day, drivers involved in single-vehicle fatal crashes are more likely to be alcohol impaired than are those drivers involved in multiple-vehicle crashes. Overall, 37 percent of drivers in single-vehicle crashes in 2009 were alcohol impaired, compared to 12 percent of those in multiple-vehicle crashes. Looking only at the hours from midnight to 3 a.m., 66 percent of drivers in single-vehicle crashes, and 37 percent of drivers in multiple-vehicle crashes, were alcohol-impaired. The most frequently recorded BAC level among drivers in fatal crashes with positive BACs was.17, more than twice the per se limit in all States, DC, and Puerto Rico. Of the 12,012 drivers with BACs of.01 or higher who were involved in fatal crashes in 2009: 10,102 (84%) had BAC levels at or above.08; and 6,685 (56%) had BAC levels at or above.15. Data for 2009 by State, for drivers involved in fatal crashes, by BAC and age groups, are shown in Table 6. The percentage of those that were alcohol-impaired is given for each age group within the State. State totals for all ages are presented in the last section of the table. Table 5 Percentage of Alcohol-Impaired (BAC.08+) Drivers Involved in Fatal Motor Vehicle Traffic Crashes, by Age Group, Gender and Year Year *All Drivers Male % 37% 32% 26% 21% 14% 8% 5% 24% % 36% 32% 27% 21% 15% 9% 6% 24% % 39% 33% 27% 22% 14% 9% 4% 24% % 38% 35% 28% 23% 15% 8% 5% 25% % 38% 36% 29% 25% 15% 8% 4% 25% Female % 19% 19% 18% 14% 7% 4% 2% 13% % 22% 20% 21% 13% 8% 5% 3% 15% % 20% 18% 17% 14% 6% 4% 2% 13% % 22% 17% 18% 13% 5% 2% 1% 13% % 23% 20% 16% 14% 7% 3% 2% 14% Source: FARS 2005 to 2008 (Final) and 2009 (ARF) *Total includes drivers under age 15 and those of unknown age.

5 5 Table 6 Drivers Involved in Fatal Crashes by Driver s BAC, Age Group, and State BAC.07 BAC.08 Total BAC.07 BAC.08 Total BAC.07 BAC.08 Total State # % # % # # % # % # # % # % # Alabama Alaska Arizona Arkansas California Colorado Connecticut Delaware Dist of Columbia Florida Georgia Hawaii Idaho Illinois Indiana Iowa Kansas Kentucky Louisiana Maine Maryland Massachusetts Michigan Minnesota Mississippi Missouri Montana Nebraska Nevada New Hampshire New Jersey New Mexico New York North Carolina North Dakota Ohio Oklahoma Oregon Pennsylvania Rhode Island South Carolina South Dakota Tennessee Texas Utah Vermont Virginia Washington West Virginia Wisconsin Wyoming National 4, ,148 3, , ,597 5, , ,610 Puerto Rico Source: FARS 2009 (ARF). National totals do not include Puerto Rico.

6 6 Table 6 (cont.) Drivers Involved in Fatal Crashes by Driver s BAC, Age Group, and State BAC.07 BAC.08 Total BAC.07 BAC.08 Total BAC.07 BAC.08 Total State # % # % # # % # % # # % # % # Alabama Alaska Arizona Arkansas California Colorado Connecticut Delaware Dist of Columbia Florida Georgia Hawaii Idaho Illinois Indiana Iowa Kansas Kentucky Louisiana Maine Maryland Massachusetts Michigan Minnesota Mississippi Missouri Montana Nebraska Nevada New Hampshire New Jersey New Mexico New York North Carolina North Dakota Ohio Oklahoma Oregon Pennsylvania Rhode Island South Carolina South Dakota Tennessee Texas Utah Vermont Virginia Washington West Virginia Wisconsin Wyoming National 5, , ,757 5, , ,664 4, ,276 Puerto Rico Source: FARS 2009 (ARF). National totals do not include Puerto Rico.

7 7 Table 6 (cont.) Drivers Involved in Fatal Crashes by Driver s BAC, Age Group, and State Total* BAC.07 BAC.08 Total BAC.07 BAC.08 Total BAC.07 BAC.08 Total Drivers Involved State # % # % # # % # % # # % # % # Alabama ,137 Alaska Arizona Arkansas California , ,180 Colorado Connecticut Delaware Dist of Columbia Florida , ,487 Georgia , ,741 Hawaii Idaho Illinois , ,296 Indiana Iowa Kansas Kentucky ,110 Louisiana ,032 Maine Maryland Massachusetts Michigan , ,239 Minnesota Mississippi Missouri ,141 Montana Nebraska Nevada New Hampshire New Jersey New Mexico New York , ,514 North Carolina , ,772 North Dakota Ohio , ,423 Oklahoma Oregon Pennsylvania , ,722 Rhode Island South Carolina ,151 South Dakota Tennessee , ,305 Texas , , ,163 Utah Vermont Virginia Washington West Virginia Wisconsin Wyoming National 2, ,868 2, ,550 35, , ,230 Puerto Rico *Total includes drivers under 15 and of unknown age. Source: FARS 2009 (ARF). National totals do not include Puerto Rico.

8 8 Summary The demographics of alcohol-impaired drivers involved in fatal crashes have remained consistent over the years. Based on 2009 FARS data: Midnight to 3 a.m. is the time with the highest percentage of alcohol-impaired drivers in fatal crashes, 55 percent. More than one-third (35%) of drivers age 21 to 24 involved in fatal crashes were alcohol-impaired, the highest of all age groups. Motorcycle riders had the highest rate of alcohol impairment (29%), and large-truck drivers (2%) the lowest rates of alcohol impairment. Passenger vehicle drivers involved in fatal crashes were alcohol-impaired 23 percent of the time. Pickup truck drivers continued to have the highest percentage (27%) of alcohol impairment among passenger vehicle drivers, while van drivers (12%) continued to be lower than that of other passenger vehicle drivers. Across all age groups, male drivers in fatal crashes were more likely than females to have been alcoholimpaired. Overall, 25 percent of male drivers and 14 percent of female drivers were alcohol-impaired. The rate of alcohol-impaired drivers involved in fatal crashes was four times higher at nighttime (36%), than during the day (9%). Drivers involved in fatal crashes were twice as likely to be alcohol-impaired on weekends (31%), than during the week (16%). Estimates of alcohol-impaired driving are generated using BAC values reported to FARS and imputed BAC values when they are not reported. For questions regarding the above reported data, contact Marie Walz, Marie.Walz@dot.gov, or Lorenzo Daniels, Lorenzo.Daniels@dot.gov. This research note and other general information on highway traffic safety may be accessed by Internet users at: www-nrd.nhtsa.dot.gov/cats/index.aspx