Duyun 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 Duyun plotted against Guizhou and China. The SNDi of new construction in Duyun peaked in 1976-1990, compared to Guizhou which peaked in 1976-1990 and China which followed a zig-zag trend with an overall increase. Most recently, Duyun's incremental SNDi fell from 2.67 to 2.04 between 1991-2005 and 2006-2020. In terms of the aggregate network, Duyun ranked 8th out of 41 cities in Guizhou and 324th 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?

• Pukou, China
• Perinthalmanna, India
• Natore, Bangladesh
• Shorsh, Iraq
• Pescara, Italy
• Obuasi, Ghana

In new street additions, Duyun and Pukou both built increasingly disconnected streets from 1975 through 1976-1990, then improved, while Shorsh built increasingly disconnected streets from 1975 through 1991-2005, then improved. For the full network, Duyun grew more disconnected from 1975 through 1991-2005, then improved, while Pukou grew more disconnected from 1975 through 1976-1990, then improved and Shorsh became progressively more disconnected. Notably, Duyun had a more connected network than Shorsh in 1975 but the two have since reversed their relative ranking.