It is not just the NUMBERS arriving and leaving, it is the type of people leaving and the type of people arriving.
Many of those leaving are either young people with skills we need for the future, or well-off business people who have had enough of this country and take their business skills elsewhere.
Whereas SOME (not all) of the people who come here are unskilled and offer us nothing except cheap labour.
Others that come here (some fake asylum seekers and illegal immigrants for example) are here purely to screw us for all they can get and many take part in organised criminal activity.
So we should be more interested in WHO is leaving and WHO is arriving, which the government seem unable to track.