Sunday 9 March 2008

Travel to Work Areas (TTWAs) [UPDATED]

The Office for National Statistics (ONS), working with Newcastle University, has produced a new set of TTWAs using a complex allocation process. The new TTWAs were defined using 2001 Census information on home and work addresses, and are based on Lower Layer Super Output areas in England and Wales, data zones in Scotland and Super Output Areas in Northern Ireland.
The fundamental criterion is that, of the resident economically active population, at least 75 per cent actually work in the area, and also, that of everyone working in the area, at least 75 per cent actually live in the area. The result is a pattern of 243 TTWAs which, although the definitive minimum working population in a TTWA is 3,500 are often much larger -- indeed, the whole of London and surrounding area forms one TTWA.

This is a significant reduction in the number of TTWAs as the trend towards more and longer distance commuting continues: in 1991 there were 314 TTWAs and in 1981 there were 334.

Further information and a downloadable PDF is here.

[UPDATE: This link returned a "not found" and search is "not currently available".
I will rectify ASAP. Hazel]

Source: BURISA Number 174 (December 2007)

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