Table 12: Percent of Long Distance Trips by Mode for Age Groups,,,,,,,,,,, ,Age group,,,,,,,,,, ,,,,,,,,,,, ,18-24 years old,Standard error,25-39 years old,Standard error,40-54 years old,Standard error,55-64 years old,Standard error,65+ years old,Standard error, Mode,,,,,,,,,,, Personal vehicle,92.0,0.83,88.9,0.66,89.1,0.48,90.4,0.65,89.4,0.78, Air,5.2,0.65,8.9,0.57,8.8,0.43,7.1,0.50,5.3,0.46, Bus,2.1,0.42,0.8,0.14,1.1,0.17,1.6,0.32,4.3,0.68, Train,0.6,0.19,1.0,0.22,0.8,0.15,0.7,0.25,0.7,0.20, Others,0.1,0.08,0.5,0.19,0.1,0.06,0.2,0.07,0.3,0.09, Total,100.0,,100.0,,100.0,,100.0,,100.0,, " NOTES: Only trips in which the transportation mode and age could be identified are included.",,,,,,,,,,, " Column totals may not add to 100 percent due to rounding.",,,,,,,,,,, Underlined estimates are based on a small sample size (<30) or a coefficient of variation greater than 30% and are not reliable. ,,,,,,,,,,, "On this table, differences are measured in columns instead of rows. Among 18-24 year olds and 55-64 year olds, the difference between the percentage using bus and ""other"" is not statistically different, nor is the difference between the percentage using train and ""other"". The difference between bus and train is statistically significant.",,,,,,,,,,, "Among those 65+, the difference between the percentage using air and bus is not statistically different, nor is the difference between the percentage using train and ""other"".",,,,,,,,,,, "SOURCE: U.S. Department of Transportation, Research and Innovative Technology Administration, Bureau of Transportation Statistics, Federal Highway Administration, National Household Travel Survey, long-distance file, 2001 (Washington, DC)",,,,,,,,,,,