Hertfordshire is an English County.
| Year | All Motor Vehicles | Cars and Taxis | Road Network Total Length |
|---|---|---|---|
| 2000 | 6,680,100,000 | 5,446,000,000 | 3,212.1 miles (5,169.4 km) |
| 2001 | 6,819,100,000 | 5,547,400,000 | 3,218.3 miles (5,179.3 km) |
| 2002 | 6,963,000,000 | 5,682,700,000 | 3,224.7 miles (5,189.7 km) |
| 2003 | 6,923,200,000 | 5,614,600,000 | 3,231.5 miles (5,200.5 km) |
| 2004 | 6,870,500,000 | 5,529,600,000 | 3,029.0 miles (4,874.7 km) |
| 2005 | 6,789,500,000 | 5,442,700,000 | 3,001.8 miles (4,831.0 km) |
| 2006 | 6,963,400,000 | 5,570,800,000 | 3,254.5 miles (5,237.6 km) |
| 2007 | 7,011,100,000 | 5,558,800,000 | 3,268.5 miles (5,260.2 km) |
| 2008 | 6,846,900,000 | 5,454,200,000 | 3,071.9 miles (4,943.7 km) |
| 2009 | 6,812,900,000 | 5,454,200,000 | 3,044.9 miles (4,900.3 km) |
| 2010 | 6,626,300,000 | 5,273,100,000 | 3,050.2 miles (4,908.8 km) |
| 2011 | 6,826,800,000 | 5,451,700,000 | 3,056.3 miles (4,918.6 km) |
| 2012 | 6,928,300,000 | 5,559,800,000 | 3,062.4 miles (4,928.4 km) |
| 2013 | 6,977,200,000 | 5,583,900,000 | 3,069.5 miles (4,940.0 km) |
| 2014 | 7,210,700,000 | 5,728,400,000 | 3,073.4 miles (4,946.2 km) |
| 2015 | 7,375,200,000 | 5,816,600,000 | 3,077.2 miles (4,952.3 km) |
| 2016 | 7,426,800,000 | 5,843,400,000 | 3,101.9 miles (4,992.1 km) |
| 2017 | 7,540,600,000 | 5,919,100,000 | 3,111.4 miles (5,007.4 km) |
| 2018 | 7,548,500,000 | 5,899,500,000 | 3,118.1 miles (5,018.2 km) |
| 2019 | 7,502,100,000 | 5,856,400,000 | 3,123.5 miles (5,026.7 km) |
| 2020 | 6,073,000,000 | 4,498,100,000 | 3,134.6 miles (5,044.6 km) |
| 2021 | 6,618,200,000 | 4,930,400,000 | 3,140.1 miles (5,053.5 km) |
| 2022 | 7,241,200,000 | 5,437,400,000 | 3,101.6 miles (4,991.5 km) |
| 2023 | 7,358,300,000 | 5,569,800,000 | 3,108.9 miles (5,003.4 km) |