Nan County in context: Street-network sprawl trends

Nan County in context

2345<19751976–19901991–20052006–2020SNDi of street additions
2345<19751976–19901991–20052006–2020SNDi of entire street network
Nan CountyHunan (Region)China (Country)

The chart above shows SNDi trends for new street additions (left panel) and the entire network (right panel), with Nan County plotted against Hunan and China. The SNDi of new construction in Nan County peaked in 1991-2005, compared to Hunan which peaked in 1976-1990 and China which followed a zig-zag trend with an overall increase. Most recently, Nan County's incremental SNDi fell from 2.17 to 1.69 between 1991-2005 and 2006-2020. In terms of the aggregate network, Nan County ranked 5th out of 89 cities in Hunan and 170th out of 1843 in China as of 2020.

New Street Additions (2006–2020)

SNDi value
1.69
Rank in China
112th of 1843
Rank in Hunan
8th of 89

Entire Network (Aggregate)

SNDi value
1.89
Rank in China
170th of 1843
Rank in Hunan
5th of 89

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

What about similarly populated cities?

1.21.82.43<19751976–19901991–20052006–2020SNDi of street additions
1.21.82.43<19751976–19901991–20052006–2020SNDi of entire street network
Nan CountyNalgondaSiguiri

In new street additions, Nan County built increasingly disconnected streets from 1975 through 1991-2005, then improved, while Nalgonda fluctuated in its street-construction patterns and Siguiri built increasingly disconnected streets over time. Looking at the full network, Nalgonda and Siguiri both became progressively more disconnected, while Nan County grew more disconnected from 1975 through 1991-2005, then improved. Notably, Nan County had a more sprawly network than Siguiri in 1975 but the two have since reversed their relative ranking.