1. Spatial dimension in the city database – coding, boundaries, revisions
Valeriya Angelova
Eurostat Unit E4
NUAC meeting
10/05/2017, Brussels

2. Content
1. The process of updating the city layer 2. City database coding and labelling system 3. Examples

3. Updating the spatial dimension
Work done so far
Update the degree of urbanisation
Consultation with NSIs (end of 2015)
Publish the updated degree of urbanisation (last version published in July 2016)
Update city list based on updated degree of urbanisation (second quarter of 2016)
Consultation with NSIs on the city list (third quarter of 2016, with Greece is still ongoing)

4. In total 79 new cities (as of May 2017)
2 cities and their FUAs (in NL and UK) have been removed

5. Updating the spatial dimension
Work done so far
Implement the updated city list in EuroBase (first quarter of 2017)
Update the FUA (started at the end of 2016)
Still waiting an input from EL, HU; to be decided on the cities in Scotland and Northern Ireland by the end of June 2017; Danish FUAs will be delivered by mid-June
In April the NSIs were asked to approve the city layer – to be published in the Statistical Atlas
No feedback from BE, LV, PL, IS, LI, NO

6. The spatial development of the HDC in the metropolitan region of Madrid

7. Cities in the metropolitan region of Madrid before and after the update

8. Key principles
All LAUs coded as 1 in degurba must be cities or part of Greater cities on the city layer (CH is an exception)
Not all cities have commuting zone hence FUA
In case of complex geographies, a Greater city can be composed of more than one city. Data will be required for the Greater city and its 'owner' only

9. Definition of FUA Step 1. Check for connected cities
If 15% of employed persons living in one city work in another city, these cities are treated as connected cities. In this case, the first city is a part of the Functional Urban Area of the second city and does not have its own FUA.
Step 2. Check for labour market flows from other municipalities
All municipalities with at least 15% of their employed residents working in a city are identified.
Step 3. Check for contiguity
The enclaves are attributed to the FUA and the exclaves are dropped.

10. Tricky cases FUA of Greater city
Commuting flows should be examined towards the entire greater city not to the city only
Municipality meeting the criteria to be a part of the FUAs of two cities
It should be assigned to the FUA to which the higher percent of the employed residents is commuting

11. The coding and labelling system for the spatial dimension - general rules
• CC Country Code
• CCxxxLa Functional Urban Area
• CCxxxKb Greater City
• CCxxxCc City
xxx is the consecutive number of the spatial unit within a given country. The Greater city and the FUA have the same number as the corresponding city;
a, b and c are version numbers
• The city and the corresponding FUA have identical label
In 2012, the version number 1 was given to cities and FUAs where no considerable changes were made compared to the previous definition and 2 was given where changes were made. Currently some cities already have a version number 4 (countries with register based commuting data are updating the FUAs every year). A new version code is needed whenever the LAU boundaries changes or an update based on the latest commuting data has led to change in the population figure higher than 1%.

12. Additional clarifications concerning the coding system
The version numbers of FUA, Greater City and city are independent of each other
Not all LAUs composing the Greater Cities are recognised as cities => no city codes
Version number '0' for FUAs codes also exists in case of city that never had a commuting zone or that lost its commuting zone ('placeholder' in the database).
It is possible to change the boundaries of a City but the Greater city level and the FUA level remains unchanged.

13. Examples from the recent recoding
• Rīga LV001L0 ->LV001L1 as commuting zone has been defined
• Alphen aan den Rijn lost its commuting zone NL026L1 -> NL026L0
• Bocholt, Stadt - new city and new code never used in EuroBase before (DE549C1)
• The city of Carrara has been removed from the city list so code IT049C1 is no longer in use in EuroBase
• Major update of all Czech FUAs – code version from 1 to 2

14. Treatment of data referring to obsoleted codes
Three options:
1. To delete data containing the old UA codes;
2. To recode the old figures using the new version codes and to flag with 'B' the first reference year when the data delivery;
3. To provide historical data.
It is not possible to keep old and new codes together in EuroBase!

15. Thank you for your attention!
Any comments?
Contact: E4