Analysis of satellite data in the 1990s identified that the average distance to forest in the continental US increased by 14% during the 1990s. Further landscape grouping identified higher forest attrition in the Western US and in public and rural lands.
Further information:S. Yang, G. Mountrakis (2017). Forest dynamics in the U.S. indicate disproportionate attrition in western forests, rural areas and public lands. PLoS ONE 12(2): e0171383. doi:10.1371/journal.pone.0171383. [2.3MB pdf]. See NY Times and Washington Post coverage here.