Decimal Day

Decimal Day (Irish: Lá Deachúil) was Monday 15 February 1971, when the United Kingdom and Ireland decimalised their £sd currencies of pounds, shillings, and pence. Until then, the British pound sterling (£) and the Irish pound (£) were divided into 20 shillings, each of 12 (old) pence, for a total of 240 pence. With decimalisation, the pound kept its old value and name in each currency, but the shilling was abolished, and the pound was divided into 100 new pence (abbreviated to "p"). In the UK, the new coins initially featured the word "new", but this would later be dropped. Each new penny was worth 2.4 old pence ("d.") in each currency. Amounts of old pence less than 6d. or 12d. did not convert exactly into multiples of (21⁄2) new pence. Conversion tables were provided, showing how prices in £sd rounded to the new currency: as an example, an old value of £7, 10 shillings and sixpence, abbreviated £7 10/6 or £7 10s 6d, became £7.521⁄2p. Coins of half a new penny were introduced in the UK and Ireland to maintain the approximate granularity of the old penny, but these were dropped in the UK in 1984 and in Ireland on 1 January 1987 as inflation reduced their value.