Translate the text from Welsh to English.



 
Heddiw, mae Cyllid a Thollau Ei Fawrhydi wedi cyhoeddi dau adroddiad dadansoddol sy'n defnyddio data treth incwm i edrych ar fudo. Comisiynwyd y dadansoddiad i hysbysu llunio polisïau treth incwm datganoledig.

Comisiynwyd y cyhoeddiad cyntaf, *Intra\-UK migration of individuals: movements in numbers and income*, gan Lywodraethau Cymru a'r Alban. Mae'n defnyddio set ddata hydredol newydd i olrhain symudiadau unigolion a'r incwm sy'n cael ei ddatgan i Gyllid a Thollau Ei Fawrhydi ar draws Cymru, yr Alban a rhannau eraill o'r Deyrnas Unedig dros amser yn seiliedig ar ddata treth gweinyddol. Mae'r dadansoddiad yn ymdrin â'r blynyddoedd 2009\-10 i 2021\-22 ac yn canfod bod Cymru a'r Alban wedi gweld cynnydd graddol mewn mewnfudiad trethdalwyr net o weddill y DU o 2016\-17 ymlaen, gyda chynnydd mwy yn 2020\-21 a 2021\-22 \- o bosibl mewn ymateb i bandemig COVID.

Mae'r ail gyhoeddiad, *Impacts of 2018\-19 Scottish Income Tax changes on intra\-UK migration and labour force participation* yn defnyddio dadansoddiad econometrig i amcangyfrif yr ymatebion i Newidiadau Treth Incwm yr Alban 2018\-19\. Yn benodol, mae'n amcangyfrif y mudo rhwng yr Alban a rhannau eraill o'r DU, ac a yw pobl wedi ymuno â'r farchnad lafur neu wedi ei gadael. Er y bu cynnydd net mewn mudo ar ôl 2018\-19, mae rhywfaint o dystiolaeth y bu gostyngiad mewn mudo net i'r Alban ymhlith unigolion sy'n ennill mwy na throthwy'r Gyfradd Uwch, gyda maint y cwymp yn cynyddu yn unol â lefelau incwm. Mae hyn yn awgrymu y byddai lefelau mudo wedi bod yn uwch heb y newidiadau i Dreth Incwm yr Alban.

Rwy'n croesawu'r ychwanegiadau hyn i'r sylfaen dystiolaeth sy'n ymwneud ag ymddygiad talwyr treth incwm ar draws y DU. Mae datblygu'r sylfaen dystiolaeth hon yn darparu gwybodaeth bwysig i helpu i lywio penderfyniadau polisi treth yn y dyfodol.







Translation:


 
Today HMRC has published two analytical reports which use income tax data to explore migration. The analysis was commissioned to inform devolved income tax policy making.

The first publication, Intra\-UK migration of individuals: movements in numbers and income, was commissioned by the Welsh and Scottish Governments. It uses a newly developed longitudinal dataset to track the movements of individuals and income declared to HMRC across Scotland, Wales and other parts of the UK over time based on administrative tax data. The analysis covers the years 2009\-10 to 2021\-22 and finds that both Wales and Scotland saw a gradual increase in net in\-migration of taxpayers from the rest of the UK from 2016\-17 onwards, with a larger uptick in 2020\-21 and 2021\-22 – possibly in response to the COVID pandemic.

The second publication, Exploring impacts of 2018\-19 Scottish Income Tax changes on intra\-UK migration and labour force participation uses econometric analysis to estimate responses to the 2018\-19 Scottish Income Tax changes. Specifically, it estimates migration between Scotland and other parts of the UK, and whether people entered or left the labour market. Although there was a net increase in migration following 2018\-19, there is some evidence of a fall in net migration to Scotland for individuals earning over the Higher Rate threshold, with the size of the fall increasing with income levels. This suggests that migration would have been higher in the absence of Scottish Income Tax changes.

I welcome these additions to the evidence base relating to the behaviour of income tax payers across the UK. The development of this evidence base provides important information to help guide future tax policy decisions.