U.S. carbon emissions from energy dropped another 1.7 percent in 2016, largely because natural gas and renewables are displacing coal in power production, data from the federal Energy Information Administration shows.

Why it matters: It's a clear signal that President Trump's effort to revive the coal industry's fortunes by cutting regulation is an uphill battle against underlying market trends.

• Total CO2 emissions are around 14 percent below 2005 levels, putting the U.S. roughly halfway toward meeting its pledge under the Paris climate accord to cut emissions by 26-28 percent by 2025.
• The emissions drop last year was smaller than the 2.7 percent decline between 2014 and 2015. Energy accounts for nearly all U.S. carbon emissions.

To be sure: Not everything is trending downward. Emissions from transportation rose by almost 2 percent last year as vehicle travel increased amid low gasoline prices. Transportation overtook the electricity sector as the largest U.S. carbon emissions source in 2016, according to EIA.