Variable

Index Meaning

Unit

I

CO₂ emissions

Ten thousand tons

P1

Population size

Ten thousand people

P2

Population urbanization rate

%

A1

Real GDP per capita

Yuan

A2

The second industry

%

A3

Private car ownership

Thousands of cars

T1

Energy intensity

Tons of standard coal per ten thousand yuan

T2

Coal consumption

Ten thousand tons of standard coal

T3

Oil consumption

Ten thousand tons of standard coal