Yi'an in context: Street-network sprawl trends

Yi'an in context

1234<19751976–19901991–20052006–2020SNDi of street additions
1234<19751976–19901991–20052006–2020SNDi of entire street network
Yi'anHeilongjiang (Region)China (Country)

The chart above shows SNDi trends for new street additions (left panel) and the entire network (right panel), with Yi'an plotted against Heilongjiang and China. The SNDi of new construction in Yi'an peaked in 1991-2005, compared to Heilongjiang which peaked in 1976-1990 and China which followed a zig-zag trend with an overall increase. Most recently, Yi'an's incremental SNDi fell from 3.2 to 1.85 between 1991-2005 and 2006-2020. In terms of the aggregate network, Yi'an ranked 5th out of 67 cities in Heilongjiang and 36th out of 1843 in China as of 2020.

New Street Additions (2006–2020)

SNDi value
1.85
Rank in China
183rd of 1843
Rank in Heilongjiang
10th of 67

Entire Network (Aggregate)

SNDi value
1.44
Rank in China
36th of 1843
Rank in Heilongjiang
5th of 67

Rankings go from most connected to most disconnected — rank 1 is the most connected.

What about similarly populated cities?

1234<19751976–19901991–20052006–2020SNDi of street additions
1234<19751976–19901991–20052006–2020SNDi of entire street network
Yi'anNing'erMahmoudiyah

In new street additions, Yi'an and Mahmoudiyah both built increasingly disconnected streets from 1975 through 1991-2005, then improved, while Ning'er fluctuated in its street-construction patterns. For the full network, Yi'an and Mahmoudiyah both became progressively more disconnected, while Ning'er grew more disconnected from 1975 through 1976-1990, then improved.