Estimated average household size is the highest for Merthyr Tydfil (2.40 persons per household), which has had the largest average household size of all local authorities in Wales since 2007.
Amcangyfrifwyd mai ym Merthyr Tudful yr oedd maint cyfartalog aelwydydd ar ei uchaf (2.40 o bobl fesul aelwyd), ac yno y bu uchaf o holl awdurdodau lleol yng Nghymru ers 2007.