Yiyang County in context: Street-network sprawl trends

Yiyang County in context

2.43.24<19751976–19901991–20052006–2020SNDi of street additions
2.43.24<19751976–19901991–20052006–2020SNDi of entire street network
Yiyang CountyHenan (Region)China (Country)

The chart above shows SNDi trends for new street additions (left panel) and the entire network (right panel), with Yiyang County plotted against Henan and China. The SNDi of new construction in Yiyang County peaked in 1976-1990, compared to Henan which peaked in 1976-1990 and China which followed a zig-zag trend with an overall increase. Most recently, Yiyang County's incremental SNDi fell from 2.96 to 1.91 between 1991-2005 and 2006-2020. In terms of the aggregate network, Yiyang County ranked 65th out of 129 cities in Henan and 566th out of 1843 in China as of 2020.

New Street Additions (2006–2020)

SNDi value
1.91
Rank in China
210th of 1843
Rank in Henan
24th of 129

Entire Network (Aggregate)

SNDi value
2.48
Rank in China
566th of 1843
Rank in Henan
65th of 129

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

What about similarly populated cities?

2345<19751976–19901991–20052006–2020SNDi of street additions
2345<19751976–19901991–20052006–2020SNDi of entire street network
Yiyang CountyJieshouItarsi

In new street additions, Yiyang County built increasingly disconnected streets from 1975 through 1976-1990, then improved, while Jieshou built increasingly disconnected streets from 1975 through 1991-2005, then improved and Itarsi built increasingly disconnected streets over time. Looking at the full network, Jieshou and Itarsi both became progressively more disconnected, while Yiyang County grew more disconnected from 1975 through 1991-2005, then improved. Yiyang County and Jieshou have been growing further apart in their street-network character since 1975.