New International Energy Agency data out Monday shows just paltry advances in global energy efficiency last year.

What they found: Primary energy intensity — that is, amount of energy needed per unit of GDP — improved by just 1.2% in 2018. That's the third consecutive year of declining gains and the slowest improvement since 2010, the agency said.

Where it stands: IEA lists several reasons for the slowdown, including...

Big structural forces, like consumer preferences for bigger cars and growth in average per-capita residential floor area.

Higher 2018 production from energy-thirsty industries in the U.S. and China.

Slowdown in the toughening of mandatory efficiency policies.

Weather, with a hot U.S. summer and a cold winter, driving up energy use.

Why it matters: Improvements in efficiency are an important tool for fighting climate change.

But IEA says the global pace is nowhere close to what's needed to help get the world on a pathway consistent with the goals of the Paris agreement.

What they're saying: “We can improve energy efficiency by 3% per year simply through the use of existing technologies and cost-effective investments," IEA executive director Fatih Birol said in a statement.