Which Chancellor of the Exchequer introduced Premium Bonds in 1956?

A Premium Bond is a lottery bond issued by the United Kingdom government's National Savings and Investments agency. The bonds are entered in a regular prize draw and the government promises to buy them back, on request, for their original price. The bonds were introduced by the Chancellor of the Exchequer Harold Macmillan in 1956.

The government pays interest on the bond (1.40% per year as at December 2017). Interest is paid into a fund from which a monthly lottery distributes tax-free prizes to bondholders whose numbers are selected randomly. The machine that generates numbers is ERNIE, for Electronic Random Number Indicator Equipment. Prizes range from £25 to £1,000,000. Between 2005 and 2009, there were two £1m prizes each month and the minimum prize was £50, but prizes were reduced after the 2009 drop in interest rates. A second £1m prize was reintroduced in August 2014.

Investors can buy bonds at any time; they have to be held for a calendar month before they qualify for a prize. Numbers are entered in the draw each month, with an equal chance of winning, until the bond is cashed.

Winners of the jackpot are told on the first working day of the month, although the actual date of the draw varies. The online prize finder is updated by the third or fourth working day of the month.