It will ensure that the country is populated by intelligent people, which will ensure that economic growth is able to continue.
Darwin was right.
It is time for the government to introduce their own method of birth control on society to ensure that the country continues to develop and be great.
I propose that we ensure that only couples with a combined income of over £40k should be allowed to have more than 2 children. This will ensure that the country is not over populated and that people are more intelligent in general, enabling greater prosperity and economic growth. Furthermore, it will also reduce unemployment with the population only increasing by those from the higher income families.