Christmas Day, 2012
The 2012 Christmas Day
holiday period begins at 6:00 p.m., Friday, December 21, and ends at 11:59
p.m., Tuesday, December 25. Our estimate of traffic fatalities for this 4.25-day
holiday period is 377 deaths with a
90% confidence interval (C.I.) of 320
to 441 deaths. Medically consulted injuries are estimated at 40,300 with
a range of 34,300 to 47,200. A medically consulted injury is an injury serious
enough that a medical professional was consulted. Medically consulted injuries
are not comparable to previous disabling injury estimates. An evaluation of
recent Christmas Day holiday period estimates is presented in Table 1 (actual
FARS data for 2011 is not yet available).
Table 1. Evaluation of Recent Christmas Day Holiday
Period Estimates
|
Year
|
Number of Days
|
Estimate
|
90% Confidence Interval
|
Actual
|
|
2006
|
3.25
|
415
|
332-507
|
379
|
|
2007
|
4.25
|
497
|
424-579
|
454
|
|
2008
|
4.25
|
432
|
371-500
|
409
|
|
2009
|
3.25
|
317
|
253-388
|
248
|
|
2010
|
3.25
|
303
|
233-384
|
249
|
Studies have shown that seat
belts are 45% effective in preventing fatalities. Although the reduction in the
risk of fatal injury from wearing seat belts is higher for light-truck
occupants at 50%, the lower figure for passenger car occupants is used in the
calculations here as the more conservative measure. The most recent data from
the Fatality Analysis Reporting System (FARS) indicate that seat belt use by
fatally injured passenger car and light truck occupants was 44.8%. Based on this information it is estimated that 138 person’s lives may be saved this
Christmas Day holiday period because they will wear their safety belts and an
additional 94 lives could be saved if all wore safety belts.
The average number of
traffic fatalities during the six most recent 4.25 day Christmas Day holiday
periods was 3.9% lower than similar
non-holiday periods (492 vs. 512 deaths). The difference is not statistically significant.
Details of the estimating
methodology and further discussion can be viewed here.
New Year’s Day, 2013
The 2013 New Year’s Day
holiday period begins at 6:00 p.m., Friday, December 28, 2012 and ends at 11:59
p.m., Tuesday, January 1, 2013. Our estimate of traffic fatalities for this 4.25-day
holiday period is 407 deaths with a
90% confidence interval (C.I.) of 347
to 475 deaths. Medically consulted injuries
are estimated at 43,500 with a range of 37,100 to 50,900. A medically consulted
injury is an injury serious enough that a medical professional was consulted.
Medically consulted injuries are not comparable to previous disabling injury
estimates. An evaluation of recent New Year’s Day holiday period estimates is
presented in Table 2 (actual FARS data for 2011 is not yet available).
Table 2. Evaluation of Recent New Year’s Day Holiday Period
Estimates
|
Year
|
Number of Days
|
Estimate
|
90% Confidence Interval
|
Actual
|
|
2006
|
3.25
|
399
|
347-457
|
432
|
|
2007
|
3.25
|
405
|
354-463
|
387
|
|
2008
|
4.25
|
498
|
447-555
|
407
|
|
2009
|
4.25
|
445
|
394-502
|
458
|
|
2010
|
3.25
|
301
|
260-347
|
286
|
Studies have shown that seat
belts are 45% effective in preventing fatalities. Although the reduction in the
risk of fatal injury from wearing seat belts is higher for light-truck
occupants at 50%, the lower figure for passenger car occupants is used in the
calculations here as the more conservative measure. The most recent data from
the Fatality Analysis Reporting System (FARS) indicate that seat belt use by
fatally injured passenger car and light truck occupants was 44.8%. Based on this information it is estimated that 149 person’s lives may be saved this
New Year’s Day holiday period because they will wear their safety belts and an
additional 101 lives could be saved if all wore safety belts.
The average number of
traffic fatalities during the six most recent 4.25 day New Year’s Day holiday
periods was 18.2% greater than similar
non-holiday periods (489 vs. 413 deaths). The difference is statistically significant at the .05 level.
Details of the estimating methodology and further discussion can be viewed here.
The terms used in the above
discussions were chosen carefully to reflect the level of accuracy of the
quantities involved. Estimate is used because the fatality figures are
calculated approximately, as opposed to the precision of calculation inferred
by the use of the word predict. May is used to indicate the
figures express a contingency, whereas will is used to express something
that may be expected or is supposed to occur.