The UPC for Gwynedd was high with a net reduction of 6,200 people across mid-2012 to mid-2021, made up of 4,100 males and 2,100 females.
Roedd UPC yn uchel ar gyfer Gwynedd, a bu gostyngiad net o 6,200 o bobl ar draws canol 2012 i ganol 2021, a oedd yn cynnwys 4,100 o wrywod a 2,100 o fenywod.