Characterizing our road system accurately, in a manner that is consistent and useful across states and over time, is a challenge. One of the biggest elements of this challenge is that the information provided in Highway Statistics (or even in HPMS) provides little insight into the dynamics of system evolution. Even to the extent that one can use arithmetic differences over time to measure change, these differences represent only net changes. These net changes may be comprised of many gross changes that may be occurring during the same time period. The trends reported in publications such as Highway Statistics may significantly mask and misrepresent the true underlying changes in the road system. For analytic and planning publications such as the Conditions and Performance Report this is problematic since an accurate representation of changes in the physical extent of the road system is compromised. Improved understanding of the gross changes in the road system can help to improve analyses and planning efforts related to national investment needs. The objective of this task was to clarify whether it is simply presentation approaches or revised reporting that is required to gain an adequate picture of trends in the mileage of the Nation's road system. In this manner, an improved statement of the size of the national highway system that does not confuse shifts from rural to urban with gains or losses in the road system can be developed.