The UK-Swiss agreement is expected to raise £1.9 billion that would otherwise largely remain beyond the reach of UK authorities.
The Office for Budget Responsibility set out the rationale for its latest estimate in its Economic and Fiscal Outlook in December 2013. It is not unusual to revise estimates.
The agreement provides for an audit process and we will be ensuring that it has been robustly implemented. Anyone who has sought to avoid the agreement still owes the evaded tax. They face severe penalties, possible criminal prosecution, and the publication of their name unless they come forward first to tell HMRC about their tax liabilities.