1921 Census of England and Wales, General Report with Appendices, Table 18 : " Distribution of 10,000 Dwellings according to size of Occupation, and Average number of Families per Dwelling in certain Administrative Counties".

Proportion per 1,000
dwellings having
Aver-
age
no. of
rooms
per
dwell-
ing.
Average number of families
per dwelling of
1-3
rooms.
4-5
rooms.
6-8
rooms.
9 rooms
and
over.
1-3
rooms.
4-5
rooms.
6-8
rooms.
9 rooms
and
over.
All
dwell-
ings.
Counties with the highest average number of rooms per dwelling:—                    
  Radnorshire 125 402 324 149 6.07 1.00 1.01 1.03 1.05 1.02
  Sussex, East 87 445 344 124 6.02 1.02 1.10 1.28 1.38 1.19
  Isle of Wight 50 469 379 102 5.97 1.00 1.02 1.05 1.11 1.04
  Middlesex 60 404 455 81 5.90 1.02 1.11 1.40 1.45 1.26
  London 181 272 423 124 5.85 1.02 1.28 1.88 2.20 1.60
  Surrey 61 515 322 102 5.84 1.02 1.08 1.16 1.13 1.11
  Sussex, West 75 508 320 97 5.81 1.00 1.04 1.12 1.18 1.08
  Devonshire 134 408 340 118 5.79 1.01 1.08 1.34 1.55 1.21
  Westmorland 148 415 341 96 5.71 1.00 1.01 1.02 1.04 1.01
  Merionethshire 175 391 322 112 5.70 1.00 1.01 1.03 1.08 1.02
                     
Counties with the lowest average number of rooms per dwelling:—                    
  Northumberland 538 312 117 33 3.78 1.03 1.09 1.11 1.13 1.06
  Durham 458 404 117 21 3.89 1.03 1.10 1.32 1.38 1.10
  Yorkshire, West Riding 340 485 152 23 4.30 1.00 1.03 1.04 1.08 1.02
  Lancashire 147 652 176 25 4.71 1.02 1.05 1.13 1.21 1.06
  Staffordshire 141 626 210 23 4.74 1.01 1.04 1.06 1.09 1.04
  Worcestershire 206 526 221 47 4.89 1.00 1.03 1.06 1.09 1.03
  Yorkshire, East Riding 195 526 230 49 4.90 1.01 1.02 1.06 1.09 1.03
  Cumberland 252 447 240 61 4.92 1.01 1.03 1.05 1.07 1.03
  Warwickshire 199 461 307 33 5.01 1.02 1.06 1.09 1.17 1.06
  Nottinghamshire 115 630 225 30 5.07 1.01 1.03 1.04 1.06 1.03
  Yorkshire, North Riding 213 488 233 66 5.07 1.03 1.05 1.05 1.09 1.05