An analysis between primary and secondary school data showed some degree of correlation but in our view, there is enough variation to support splitting the indicator.
Dangosodd dadansoddiad o ddata ysgolion cynradd ac uwchradd rywfaint o gydberthyniad rhyngddynt ond, yn ein barn ni, mae digon o amrywiad i gyfiawnhau rhannu'r dangosydd yn ddau.