Derby in context: Street-network sprawl trends

Derby in context

33.64.24.8<19751976–19901991–20052006–2020SNDi of street additions
33.64.24.8<19751976–19901991–20052006–2020SNDi of entire street network
DerbyEngland (Region)United Kingdom (Country)

The chart above shows SNDi trends for new street additions (left panel) and the entire network (right panel), with Derby plotted against England and United Kingdom. All three follow the same trend in new construction, suggesting a shared regional pattern of development. Most recently, Derby's incremental SNDi fell from 4.26 to 3.87 between 1991-2005 and 2006-2020. In terms of the aggregate network, Derby ranked 25th out of 124 cities in England and 31st out of 143 in United Kingdom as of 2020.

New Street Additions (2006–2020)

SNDi value
3.87
Rank in United Kingdom
61st of 143
Rank in England
55th of 124

Entire Network (Aggregate)

SNDi value
3.2
Rank in United Kingdom
31st of 143
Rank in England
25th of 124

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

What about similarly populated cities?

2.12.83.54.2<19751976–19901991–20052006–2020SNDi of street additions
2.12.83.54.2<19751976–19901991–20052006–2020SNDi of entire street network
DerbyChernivtsiSiem Reap

In new street additions, Derby built increasingly disconnected streets from 1975 through 1991-2005, then improved, while Chernivtsi built increasingly disconnected streets over time and Siem Reap built increasingly connected streets from 1975 through 1991-2005, then shifted to more disconnected patterns. For the full network, Derby and Chernivtsi both became progressively more disconnected, while Siem Reap became more connected from 1975 through 1991-2005, then grew more sprawly from 1991-2005 onwards. Derby and Siem Reap have been converging in their street-network character since 1975.