Index interval

Level

State Interpretation

[0, 2)

Smooth

There is basically no congestion. You can drive according to the road speed limit.

[2, 4)

Basic smooth

A small amount of congestion, you need 0.2 to 0.5 times longer than smooth traffic.

[4, 6)

Mild congestion

Some roads, you need more than 0.5 to 0.8 times longer than unblocked traffic.

[6, 8)

Moderate congestion

A large number of roads, you need more than 0.8 to 1.1 times longer than smooth traffic.

[8, 10)

Severe congestion

Most of the city’s road are congested, you need 1.1 times more than smooth.