In contrast, the Welsh Tax Acts permit only tax rates and tax bands to be changed by regulations subject to the made affirmative procedure.
I'r gwrthwyneb, dim ond cyfraddau treth a bandiau treth y mae Deddfau Trethi Cymru yn caniatáu iddynt gael eu newid drwy reoliadau sy'n ddarostyngedig i'r weithdrefn gadarnhaol ‘gwnaed’.