**Estimates for the number of CDL and nonCDL Drivers in the National
Fleet,**

**Based on May 2005 MCMIS Data and 2003 Drug&Alcohol Survey**

*Richard Gruberg, FMCSA Analysis Division 6/15/05*

Estimates for the total number of CDL and nonCDL drivers are given in
Table 1.

Table 1. Total Number of Drivers in National Fleet, by Driver Category

  ----------------------------------- -----------------------------------
  Driver Category                     Estimated Number of Drivers

  CDL Drivers                         4.2 Million

  NonCDL Interstate Drivers           1.3 Million

  NonCDL Intrastate Drivers           1.5Million

  Total Drivers                       7.0 Million
  ----------------------------------- -----------------------------------

The estimates in Table 1 were obtained as follows:

# CDL Drivers

An estimate for the total number of CDL drivers was obtained by taking
the estimate from the 2003 Drug and Alcohol Testing Survey for the total
number of CDL drivers, and adjusting this number upwards, to account for
the fact that the sampling frame for this survey (FMCSA's Motor Carrier
Management Information System Census File) does not capture most
intrastate carriers, many of which have CDL drivers as well.

The unadjusted estimate from this survey was 3.3 million CDL drivers. To
adjust this estimate, an analysis was performed on the FMCSA Census
File, the sampling frame used for the survey. This file is a listing of
all motor carriers that have a U.S. DOT number. Although, traditionally,
only interstate carriers have been required to obtain a U.S. DOT number,
a handful of states are now requiring their intrastate carriers to also
apply to the FMCSA for a U.S. DOT number. An analysis of the file
indicated that in the following states, a large percentage of the U.S.
DOT numbers issued belonged to intrastate carriers: Colorado, Florida,
Georgia, Kentucky, Minnesota, and Wisconsin. In these states, it was
found that slightly over 26% of the total drivers captured by the data
file were engaged in intrastate non-hazmat operations. It was thus
assumed that these states were requiring their intrastate carriers to
obtain U.S. DOT numbers.

Based on the results of this analysis, the total estimate for CDL
drivers obtained from the Drug and Alcohol Testing Survey was broken
down into two components, the first component being the total number CDL
drivers belonging to carriers located in the six states referenced
above, and the second component being the total number of drivers
belonging to carriers in the remaining 45 states. It was estimated that
roughly 800,000 CDL drivers came from these six states and 2.5 million
CDL drivers came from the remaining 45 states. The estimate for the
total number of drivers from the 6 states was not adjusted, as the
sampling frame for the survey was already capturing both interstate and
intrastate carriers. The estimate for the total number of drivers in the
remaining states, however, was adjusted upwards to account for the fact
that the sampling frame was not capturing the intrastate nonhazmat
carriers in these states. Specifically, it was assumed here that the
true ratio of intrastate CDL drivers to all CDL drivers (both intrastate
and interstate) in the remaining 45 states was equal to 0.26 (see
above), as was the case in the other 6 states (CO, FL, GA, KY, MN, WI).
This relationship implied an additional 850,000 million intrastate CDL
drivers not captured by the survey in these states, thus yielding an
adjusted total estimate of 4.2 million CDL drivers, including those
belonging to both interstate and "intrastate only" carriers.

# NonCDL Interstate Drivers

An estimate for the total number of nonCDL interstate drivers was taken
directly from the MCMIS Census file, by summing-up the total number of
drivers in the file belonging to active interstate carriers. This total
was found to be approximately 1.3 million drivers.

# NonCDL Intrastate Drivers

An estimate for the total number of nonCDL intrastate drivers was
obtained by, first, estimating the total number of nonCDL drivers, and
then by subtracting from this number the estimate for the number of
nonCDL interstate drivers (see above).

An analysis of the MCMIS Census File indicated that in the six states of
CO, FL, GA, KY, MN, and WI (states believed to be complete in the
reporting to MCMIS for both inter- and intrastate carriers), the ratio
of total nonCDL to total CDL drivers was found to be 1.2. Based on this
finding, the adjusted estimate for total CDL drivers (see above) was
multiplied by 0.67, yielding of a total of 2.8 million nonCDL drivers.

To obtain the estimate of nonCDL intrastate drivers, the previous
estimate of 1.3 million nonCDL interstate drivers was subtracted from
the estimated 2.8 million total nonCDL drivers, yielding a total of 1.5
million nonCDL intrastate drivers.

Revised 6/15/05