Viên An 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 Viên An plotted against Hà Nội and Vietnam. The SNDi of new construction in Viên An was at its lowest in 1976-1990, compared to Hà Nội which peaked in 1991-2005 and Vietnam which rose steadily. Most recently, Viên An's incremental SNDi rose from 4.84 to 5.45 between 1991-2005 and 2006-2020. In terms of the aggregate network, Viên An ranked 6th out of 9 cities in Hà Nội and 90th out of 126 in Vietnam as of 2020.

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

What about similarly populated cities?

• Bharwari, India
• Hanggin Rear Banner, China
• Matehuala, México
• Uzun, Uzbekistan
• Qebchaq, Iran
• Polvilho, Brazil

In new street additions, Viên An built increasingly connected streets from 1975 through 1976-1990, then shifted to more disconnected patterns, while Bharwari built increasingly connected streets over time and Uzun built increasingly disconnected streets over time. For the full network, Viên An became more connected from 1975 through 1976-1990, then grew more sprawly from 1976-1990 onwards, while Bharwari became progressively more connected and Uzun became progressively more disconnected. Notably, Viên An had a more sprawly network than Uzun in 1975 but the two have since reversed their relative ranking.