Commuting flows

[Docere]

Data here on commuting to London by local authority (the London Magnet) from 2011

https://fryford.github.io/dvc193/indexv3...d&view=440,200,160,160&tr=NaN,NaN&sc=NaN

[Yuri]

Every definition based on commute flows is also misleading as you need to settle an arbitrary parameter as reference.

Take London, for example, with a relatively big city proper. What should be the reference from which we measure commute flows in and out? Inner London, Greater London, London UA? Where to draw a line.

Or in the US? What is "Los Angeles" from which I'll measure the commute? Los Angeles the city, Los Angeles the basin, Los Angeles the county?

[New Brisavoine]

The international FUA definition of metro areas has a harmonized definition for that: it's neither the city proper nor the urban area. It's a core defined by high density (more than 1,500 inh. per km²). Administrative borders are irrelevant.

[Yuri]

Originally Posted by New Brisavoine

The international FUA definition of metro areas has a harmonized definition for that: it's neither the city proper nor the urban area. It's a core defined by high density (more than 1,500 inh. per km²). Administrative borders are irrelevant.

Could you give me an example? What's London core used by them? With such relatively low density, London's core goes way beyond Greater London. Could you tell me what's São Paulo's core to help me to understand? Or Los Angeles'?

[New Brisavoine]

Originally Posted by Yuri

Could you give me an example? What's London core used by them? With such relatively low density, London's core goes way beyond Greater London. Could you tell me what's São Paulo's core to help me to understand? Or Los Angeles'?

The London core of the FUA is: Greater London + the districts/UAs of Basildon, Chelmsford, Gravesham, and Thurrock. That's a territory of 2,284 km² continaing 9.76 million people in 2024.

For São Paulo, Brazil is not part of the OECD, so they don't calculate it, but this paper has estimated the FUAs of non-OECD countries, and for Brazil they've found that the FUAs are very similar to IBGE's arranjos populacionais. In the case of São Paulo, the FUA as delineated in their paper is 96% similar to the arranjo populacional de São Paulo.

[Docere]

Some data on "divided loyalty" counties:

Mercer County is its own MSA and part of the NYC CSA. 23% commute to the NYC MSA, 8% to the Philadelphia MSA.

Howard County MD is part of Baltimore MSA but also has strong commuting ties to the DC metro. 29% commute to other Baltimore MSA counties, 23% to the Washington MSA.

[iheartthed]

Originally Posted by Docere

Some data on "divided loyalty" counties:

Mercer County is its own MSA and part of the NYC CSA. 23% commute to the NYC MSA, 8% to the Philadelphia MSA.

Isn't 23% well above the threshold to be included in the MSA?

[Steely Dan]

Originally Posted by Docere

Some data on "divided loyalty" counties:

Mercer County is its own MSA and part of the NYC CSA. 23% commute to the NYC MSA, 8% to the Philadelphia MSA.

Howard County MD is part of Baltimore MSA but also has strong commuting ties to the DC metro. 29% commute to other Baltimore MSA counties, 23% to the Washington MSA.

Where do you find this info?

I'd love to see the splits for Kenosha and Racine counties, each of which are their own MSAs now, tucked between Chicaoland and Milwaukeeland.

[Docere]

OP first link.

Kenosha is part of the Chicago CSA, with around 24% commuting to Chicago MSA and just 5% to Milwaukee MSA (I say "around" because I'm not including the flows of under 100).

[Docere]

Originally Posted by iheartthed

Isn't 23% well above the threshold to be included in the MSA?

It's 25% commuting to the "central counties", so just short. CSAs are combined MSAs that have interchanges of 15% (A to B + B to A).

[Steely Dan]

Originally Posted by Docere

OP first link.

Thanks!

I really like the symmetry of how Kenosha and Racine split between Chicago and Milwaukee.

And how both of them barely miss the 25% MSA inclusion threshold by just a hair.


Kenosha County to Chicago MSA: 24.0%
Kenosha County to Racine MSA: 10.9%
Kenosha County to Milwaukee MSA: 5.4%

Racine County to Milwaukee MSA: 23.7%
Racine County to Kenosha MSA: 9.7%
Racine County to Chicago MSA: 3.2%


In a vaccuum where Milwaukee and Racine don't exist north of Kenosha County, it would almost certainly be in Chicago's MSA.

And conversely, in a vacuum where Chicago and Kenosha don't exist south of Racine County, it would almost certainly be in Milwaukee's MSA.

A classic case of tweener counties getting pulled in two different directions, such that neither meets the 25% to be in their parent MSA.

[Docere]

We often hear about Golden Greater Horseshoe around Toronto being the "equivalent" of a CSA but it isn't really.

Map of GGH: https://www.ontario.ca/page/planning-transportation-greater-golden-horseshoe

% commuting to Greater Toronto Area (Toronto and 4 surrounding regional municipalities):

Dufferin 39.7%
Kawartha Lakes 28.8%
Hamilton 22.9%
Simcoe 21.2%
Northumberland 18.8%
Wellington 12.5%
Peterborough 8.8%
Niagara 6.3%
Brant 6.3%
Waterloo 5.4%
Haldimand-Norfolk 4.1%

Only Hamilton and Simcoe County really has strong commuting ties to the GTA (and Simcoe is rather large, south of Barrie is basically GTA exurbs). Waterloo and Niagara connections are rather limited. Dufferin County and Kawartha Lakes would be "outlying counties" using US Census Bureau criteria.

[Docere]

About a decade old but lots here on NYC commuting.

https://www.nyc.gov/assets/planning/down...economy/nyc-ins-and-out-of-commuting.pdf


# of NYC in-commuters by region:

Inner NJ 373,000
Long Island 289,000
Lower Hudson 183,000
Outer NJ 50,000
Connecticut 43,000
Mid-Hudson 34,000

% commute to NYC:

Hudson 31%
Nassau 31%
Westchester 31%
Bergen 20%
Putnam 18%
Rockland 17%
Essex 14%
Orange 11%
Suffolk 11%
Middlesex 10%
Monmouth 10%
Union 10%
Fairfield 8%
Dutchess 7%
Morris 7%
Mercer 5%
Passaic 5%
Sullivan-Ulster 5%
Litchfield 3%
Hunterdon 2%
Ocean 2%
Sussex 2%
New Haven 1%
Warren 1%

Manhattan workers, place of residence:

Manhattan 29%
Outer boroughs 45%
NYC region 26%

NYC in-Commuters in Manhattan, subregion of residence:

North NJ 53%
Long Island 23%
Hudson Valley 21%
Connecticut 5%

Office workers as a percentage of Manhattan workers by place of residence:

NYC 38%
NYC region 51%

[Docere]

Can't find commuting flow data for UK, but have a sort of proxy measure using number of Greater London commuters and 60% of local population as a denominator. This is 2011 data so it would be great to see more recent commuting data.

Number of Greater London commuters / est commuting share, local authorities:

Epsom and Ewell (Surrey) 15,800 31.6%
Epping Forest (Essex) 25,900 31.4%
Spelthorne (Surrey) 18,000 28%
Elmbridge (Surrey) 23,800 27.9%
Hertsmere (Hertfordshire) 18,000 27.2%
Brentwood (Essex) 12,800 26.9%
Dartford (Kent) 19,100 25.5%
Sevenoaks (Kent) 18,400 25%
Broxbourne (Hertfordshire) 14,400 23.6%
Tandridge (Surrey) 12,500 23%
Three Rivers (Hertfordshire) 13,100 22.8%
Thurrock (Essex) 22,100 20.4%
Watford (Hertfordshire) 11,700 19.1%
St. Albans (Hertfordshire) 16,600 18.8%
Reigate and Banstead (Surrey) 17,500 18.3%
Gravesham (Kent) 10,300 15.5%
Basildon (Essex) 17,800 15.3%
East Hertfordshire (Hertfordshire) 12,800 13.6%
Slough (Berkshire) 13,200 13.1%
Chelmsford (Essex) 14,100 12.4%
Windsor and Maidenhead (Berkshire) 11,100 11.6%
Southend-on-Sea (Essex) 12,400 11.2%
Dacorum (Hertfordshire) 10,200 10.5%
Medway (Kent) 17,300 9.9%