National Insurance number
The National Insurance number is a number used in the United Kingdom in the administration of the National Insurance or social security system. It is also used for some purposes in the UK tax system. The number is described by the United Kingdom government as a "personal account number".
Office of the Chief Actuary
The Office of the Chief Actuary is a government agency that has responsibility for actuarial estimates regarding social welfare programs. In Canada, the Office of the Chief Actuary works with the Canada Pension Plan and the Old Age Security Program. In the United States, both the Social Security Administration and the Centers for Medicare and Medicaid Services have an Office of the Chief Actuary that deals with Social Security and Medicare, respectively. A similar agency in the United Kingdom is called the Government Actuary's Department (GAD).