; and (B) to net zero emissions by the year 2050. (4) According to a report by the Environmental Protection Agency entitled Inventory of U.S. Greenhouse Gas Emissions and Sinks , transportation activities accounted for the largest portion (approximately 29.9 percent) of total greenhouse gas emissions in the United States in 2017. (5) The Secretary of Transportation has a leading role in reducing United States greenhouse gas emissions since transportation activities continue to account for a large portion of total greenhouse gas emissions in the United States. (6) Reducing greenhouse gas emissions will demonstrate adherence to the commitments of the United States under the Paris Agreement, and any other similar international climate change agreements. 3. National Strategic Action Plan to reduce greenhouse gas emissions (a) Requirement Not later than 2 years after the date of enactment of this Act, the Secretary, using the best available science and in collaboration with the Administrator of the Environmental Protection Agency, shall publish an action plan known as the National Strategic Action Plan (in this Act referred to as the action plan ) to reduce greenhouse gas emissions in the transportation sector to the emissions target by the year 2040. (b) Content The action plan may include— (1) The implementation of strategies that increase the usage of passenger rail, public transportation systems, walking, cycling, and other low-carbon modes of transportation including— (A) improvements to infrastructure; and (B) changes to engineering and design guidelines, including the Manual on Uniform Control Devices for Streets and Highways or current design criteria codified under part 625, title 23 of the United States Code of Federal Regulations. (2) Strategies and policies that reduce Vehicle Miles Traveled (VMT), including— (A) the promotion of transit oriented or transit accessible development; (B) access to jobs and services as a metric to measure transportation success instead of level of service