Short term, quarterly changes can be volatile, although are presented here given the impacts of EU Exit and the COVID-19 pandemic on trade.
Gall newidiadau tymor byr, chwarterol fod yn gyfnewidiol, er eu bod yn cael eu cyflwyno yma o ystyried effeithiau Ymadael â'r UE a’r pandemig COVID-19 ar fasnach.