Immigration was never going to change post brexit as neither Lobour nor the Consevatives were going to reduce it, Farage did use the unemployed and low paid to further his wealth
The population of British more than 1st generation has been dropping for various reasons for more than a decade yet the population of Briton has been climbing, it`s highest ever if i am not mistaken, now if you want to use figures use the full decade not just the Polish returning home who had no intention of staying here, we need immigration but it should be what we need