Ya'an in context: Street-network sprawl trends

Ya'an in context

2.43.244.8<19751976–19901991–20052006–2020SNDi of street additions
2.43.244.8<19751976–19901991–20052006–2020SNDi of entire street network
Ya'anSichuan (Region)China (Country)

The chart above shows SNDi trends for new street additions (left panel) and the entire network (right panel), with Ya'an plotted against Sichuan and China. All three follow the same trend in new construction, suggesting a shared regional pattern of development. Most recently, Ya'an's incremental SNDi rose from 3.54 to 4.44 between 1991-2005 and 2006-2020. In terms of the aggregate network, Ya'an ranked 63rd out of 98 cities in Sichuan and 1319th out of 1843 in China as of 2020.

New Street Additions (2006–2020)

SNDi value
4.44
Rank in China
1515th of 1843
Rank in Sichuan
75th of 98

Entire Network (Aggregate)

SNDi value
3.42
Rank in China
1319th of 1843
Rank in Sichuan
63rd of 98

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

What about similarly populated cities?

1.82.73.64.5<19751976–19901991–20052006–2020SNDi of street additions
1.82.73.64.5<19751976–19901991–20052006–2020SNDi of entire street network
Ya'anGaoyouVigo

In new street additions, Ya'an fluctuated in its street-construction patterns, while Gaoyou fluctuated in its street-construction patterns and Vigo built increasingly disconnected streets from 1975 through 1976-1990, then improved. For the full network, Ya'an became progressively more disconnected, while Gaoyou fluctuated in connectivity and Vigo grew more disconnected from 1975 through 1991-2005, then improved. Notably, Ya'an had a more connected network than Gaoyou in 1975 but the two have since reversed their relative ranking.