Responses they had had imputed into the previous survey year (Year 3) based on turnover they had reported in the years prior to that (e.g. Year 2) [ footnote 10 ].
Ymatebion yr oeddent wedi’u priodoli i’r flwyddyn arolwg flaenorol (Blwyddyn 3) yn seiliedig ar drosiant yr oeddent wedi’i adrodd yn y blynyddoedd cyn hynny (e.e.