Vector boundaries and population figures for 1991 for the Enumeration Districts of Great Britain

Table ID:
ENUMD_1991_GB     (1247730)
Contents:
Vector boundaries and population figures for 1991 for the Enumeration Districts of Great Britain
Approx. number of rows:
147,904
Table type:
Raw Data
Documentation Author:
Paula Aucott
Chronology:
The data are for the single year 1991.

Sources:

  1. The polygons and identifiers for 1991 were obtained via the Census Geography service provided by the UK Data Service Census Support (formerly known as the Edina UKBorders service).
  2. The 1991 population figures were obtained via Casweb, a service provided by the UK Data Service Census Support. This service gives access to historical aggregated small area census statistics for Great Britain between 1971 and 2001.


Notes:

  1. In 1991 Census data for England and Wales was collected as Enumeration Districts and as Output Areas in Scotland.
  2. The polygon data file was a compilation of three separate files, Enumeration Districts for England and for Wales plus Output Areas for Scotland using the Geo-processing > merge function in ArcGIS.
  3. The statistical data was linked to the polygon data via the "join data" function using the "join attributes from a table" option on the unit "Label" (England and Wales) or "Zone_ID" (Scotland). The resulting temporarily joint table was then exported to a new permenant polygon coverage including these datasets. The statistical data contained units such those identified as "shipping" which did not correspond to any polygon area and consequently could not be matched up and included with the polygons in ArcGIS.
  4. This coverage was re-projected from the British national grid to the European projection used throughout the database, ETRS89 LCC (Lambert Conformal Conic) in ArcGIS using the Data Management Tools > Projections and Transformations > Feature > Project function.
  5. The EU's preference was for counts of 'Usually Resident', but this was not available for some earlier years therefore we have included both 'Persons Present' and 'Usually Resident' wherever possible.
  6. The area for each polygon was generated using the 'Calculcate Geometry' function in ArcGIS.


Checking:

  1. The original data supplied by the UK Data Service were not checked other than making sure each polygon matched a row in the statsitical data.


Indices:

IndexTypeColumn(s) indexed
enumd_1991_gb_pkey Primary key gid
enumd_1991_gb_g_foot_etrs_gist   g_foot_etrs


Constraints:

The table has the following associated constraints:

ConstraintTypeDetails
enumd_1991_gb_pkey Primary Key See details above for primary key index
enforce_dims_g_foot_etrs Check ((st_ndims(g_foot_etrs) = 2))
enforce_geotype_g_foot_etrs Check (((geometrytype(g_foot_etrs) = 'MULTIPOLYGON'::text) OR (g_foot_etrs IS NULL)))
enforce_srid_g_foot_etrs Check ((st_srid(g_foot_etrs) = 3034))



Columns within table:

ColumnTypeContents
gid Integer number. Unique row identifier
zone_label Text string (max.len.=24). Enumeration District or Output Area ID number defined by ONS or GROS as supplied.
ed_area_sqm float8 Area of polygon in square metres, calculated by us in ArcGIS from the polygon.
all_pres_res Integer number. Residents present within the Enumeration District/Output Area in 1991.
abs_res_part Integer number. Residents absent within the Enumeration District/Output Area in 1991 where part of the household was present.
abs_res_whole Integer number. Residents absent within the Enumeration District/Output Area in 1991 where the none of the household was present, but household was enumerated.
abs_res_impu Integer number. Residents absent within the Enumeration District/Output Area in 1991 where the none of the household was present and household was imputed.
all_visitors Integer number. All visitors within the Enumeration District/Output Area in 1991.
visitors_uk Integer number. Visitors within the Enumeration District/Output Area in 1991 normally resident in the United Kingdom.
visitors_non_uk Integer number. Visitors within the Enumeration District/Output Area in 1991 not normally resident in the United Kingdom.
pers_present_71 Integer number. Persons present within Enumeration District/Output Area in 1991, based on 'Present residents'and 'Visitors'. This is the baseline for the equivalent of the population present figure in 1971.
pers_present_81 Integer number. Persons usually resident within Enumeration District/Output Area in 1991, based on 'Present residents' and 'Absent residents (part of household present)'. This is baseline for the equivalent of the population usually resident figure in 1981.
pers_present_91 Integer number. Persons usually resident within Enumeration District/Output Area in 1991, based on 'Present residents' and a combination of all 'Absent residents' figures. This is the baseline provided for producing equivalent figures for the 1991 population.
g_foot_etrs geometry Boundary polgon, as supplied by the EUK Data Service.