Zuoyun in context: Street-network sprawl trends

The chart above shows SNDi trends for new street additions (left panel) and the entire network (right panel), with Zuoyun plotted against Shanxi and China. The SNDi of new construction in Zuoyun was at its lowest in 1976-1990, compared to Shanxi which followed a zig-zag trend with an overall increase and China which followed a zig-zag trend with an overall increase. Most recently, Zuoyun's incremental SNDi rose from 3.1 to 3.51 between 1991-2005 and 2006-2020. In terms of the aggregate network, Zuoyun ranked 47th out of 80 cities in Shanxi and 1226th out of 1843 in China as of 2020.

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

What about similarly populated cities?

• Domkal, India
• Shanyang, China
• Fangxian, China
• Benidorm, Spain
• Chalchuapa, El Salvador
• Vĩnh Trụ, Vietnam

In new street additions, Zuoyun built increasingly connected streets from 1975 through 1976-1990, then shifted to more disconnected patterns, while Domkal built increasingly disconnected streets over time and Benidorm fluctuated in its street-construction patterns. Looking at the full network, Domkal and Benidorm both became progressively more disconnected, while Zuoyun became more connected from 1975 through 1991-2005, then grew more sprawly from 1991-2005 onwards. Notably, Zuoyun had a more sprawly network than Domkal in 1975 but the two have since reversed their relative ranking.