Tongzi in context: Street-network sprawl trends

Tongzi in context

3.544.55<19751976–19901991–20052006–2020SNDi of street additions
3.544.55<19751976–19901991–20052006–2020SNDi of entire street network
TongziGuizhou (Region)China (Country)

The chart above shows SNDi trends for new street additions (left panel) and the entire network (right panel), with Tongzi plotted against Guizhou and China. While Guizhou and China both followed a zig-zag trend with an overall increase, Tongzi's new street additions followed a zig-zag trend with an overall decrease. Most recently, Tongzi's incremental SNDi rose from 3.28 to 3.59 between 1991-2005 and 2006-2020. In terms of the aggregate network, Tongzi ranked 29th out of 41 cities in Guizhou and 1536th out of 1843 in China as of 2020.

New Street Additions (2006–2020)

SNDi value
3.59
Rank in China
1182nd of 1843
Rank in Guizhou
24th of 41

Entire Network (Aggregate)

SNDi value
3.95
Rank in China
1536th of 1843
Rank in Guizhou
29th of 41

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

What about similarly populated cities?

23456<19751976–19901991–20052006–2020SNDi of street additions
23456<19751976–19901991–20052006–2020SNDi of entire street network
TongziLahatHengyang

In new street additions, Tongzi and Lahat both fluctuated in its street-construction patterns, while Hengyang built increasingly disconnected streets from 1975 through 1976-1990, then improved. For the full network, Tongzi grew more disconnected from 1975 through 1976-1990, then improved, while Lahat became progressively more disconnected and Hengyang grew more disconnected from 1975 through 1991-2005, then improved. Notably, Tongzi had a more sprawly network than Lahat in 1975 but the two have since reversed their relative ranking.