Some of the figures you requested Grevase.The components of immigration
12. The three major components are:

Economic migration.
The present government have trebled the number of work permits issued from 43,000 in 1997 to 129,000 in 2007. Dependants are additional.
Family reunion.
The government changed the rules in June 1997 to permit marriage to be used as a means of immigration. The numbers have since risen by 50% to about 42,000 a year.
Asylum.
The government have sought to tighten the system and have made a number of improvements. However, they are still not removing as many as are rejected each year so the pool of illegal immigrants continues to grow. Applications are currently running at about 30,000 a year.
Illegal immigration
13. There are three main sources of illegal immigration - those who enter illegally on the back of a truck, visitors and students who overstay their visas, and rejected asylum seekers who the authorities fail to remove.

14. In June 2005, a government commissioned study gave a central estimate of 430,000. Migrationwatch updated this to 475,000 (Briefing Paper 11.6). In March 2009 a study by the London School of Economics suggested a central estimate of 725,000 of which 518,000 were thought to be in London. The government continue to be opposed to an amnesty - for good reasons (Briefing Paper 11.7).

The briefing papers were issued by Migration Watch.