The illegal global trade in ivory has shrunk while the trafficking of pangolins has soared, a UN report on wildlife crime based on four years' data said on Friday. National bans on selling ivory, particularly China's in 2017, appear to have helped further erode ivory trafficking after it peaked around 2011-2013, the United Nations Office on Drugs and Crime (UNODC) said in its World Wildlife Crime Report, which was last published in 2016.