DfT changed data collection methods for domestic road freight statistics from a paper-based to online survey midway through 2021.
Newidiodd yr Adran Drafnidiaeth ei dull o gasglu data ar gyfer ystadegau ar gludo nwyddau ffyrdd gan gerbydau domestig yn unig o arolwg papur i arolwg ar-lein hanner ffordd drwy 2021.