Due to the relatively small proportion of returns that are received in paper format (less than 2%), this omission is not considered to have a material effect on the year-end numbers.
Oherwydd y gyfran gymharol fach ffurflenni treth a dderbynnir ar ffurf papur (llai na 2%), ni ystyrir y caiff yr hepgoriad hwn effaith arwyddocaol ar y rhifau ar ddiwedd y flwyddyn.