Housing costs include rents, mortgage interest and capital repayments, water and sewerage rates, structural insurance cover, service charges and council tax (net of rebates).
Mae costau tai yn cynnwys rhenti, llog morgais ac ad-daliadau cyfalaf, trethi dŵr a charthffosiaeth, sicrwydd yswiriant strwythurol, taliadau gwasanaeth a threth gyngor (net o ad-daliadau).