Carmarthenshire is a Welsh Unitary Authority.
| Year | All Motor Vehicles | Cars and Taxis | Road Network Total Length |
|---|---|---|---|
| 2000 | 1,014,200,000 | 789,900,000 | 2,221.1 miles (3,574.5 km) |
| 2001 | 1,004,400,000 | 782,900,000 | 2,224.1 miles (3,579.4 km) |
| 2002 | 1,059,600,000 | 825,000,000 | 2,227.2 miles (3,584.4 km) |
| 2003 | 1,071,900,000 | 842,500,000 | 2,230.4 miles (3,589.5 km) |
| 2004 | 1,079,200,000 | 852,700,000 | 2,230.5 miles (3,589.6 km) |
| 2005 | 1,096,800,000 | 852,000,000 | 2,218.5 miles (3,570.3 km) |
| 2006 | 1,170,800,000 | 905,100,000 | 2,217.4 miles (3,568.5 km) |
| 2007 | 1,199,600,000 | 919,300,000 | 2,217.2 miles (3,568.3 km) |
| 2008 | 1,197,300,000 | 909,300,000 | 2,217.7 miles (3,569.1 km) |
| 2009 | 1,171,500,000 | 894,700,000 | 2,216.5 miles (3,567.1 km) |
| 2010 | 1,153,400,000 | 873,000,000 | 2,215.5 miles (3,565.5 km) |
| 2011 | 1,139,300,000 | 861,600,000 | 2,215.5 miles (3,565.5 km) |
| 2012 | 1,146,000,000 | 864,900,000 | 2,217.4 miles (3,568.6 km) |
| 2013 | 1,173,700,000 | 887,300,000 | 2,217.8 miles (3,569.3 km) |
| 2014 | 1,216,100,000 | 922,300,000 | 2,218.0 miles (3,569.6 km) |
| 2015 | 1,232,300,000 | 928,400,000 | 2,221.9 miles (3,575.8 km) |
| 2016 | 1,300,100,000 | 979,900,000 | 2,221.8 miles (3,575.6 km) |
| 2017 | 1,305,100,000 | 975,300,000 | 2,219.2 miles (3,571.5 km) |
| 2018 | 1,313,000,000 | 975,300,000 | 2,216.4 miles (3,567.0 km) |
| 2019 | 1,314,400,000 | 974,100,000 | 2,218.8 miles (3,570.8 km) |
| 2020 | 998,100,000 | 712,500,000 | 2,221.1 miles (3,574.5 km) |
| 2021 | 1,125,000,000 | 798,500,000 | 2,217.9 miles (3,569.4 km) |
| 2022 | 1,240,300,000 | 896,300,000 | 2,218.9 miles (3,571.0 km) |
| 2023 | 1,267,600,000 | 928,600,000 | 2,220.6 miles (3,573.7 km) |