Decimalisation

This article is about decimalisation of currency and measurement. For the system of library classification, seeDewey Decimal Classification.For the development of the number system, seeDecimal.

Decimalisationordecimalization(seespelling differences) is the conversion of a system of currency or of weights and measures to units related bypowers of 10.

Most countries have decimalised their currencies, converting them from non-decimal sub-units to adecimalsystem, with one basic currency unit and sub-units that are to a power of10,most commonly 100, and exceptionally 1000; and sometimes at the same time changing the name of the currency or the conversion rate to the new currency. Today, only two countries have non-decimal currencies:Mauritania,where 1ouguiya= 5khoums,andMadagascar,where 1ariary= 5iraimbilanja.However, these are only theoretically non-decimal, as, in both cases, the value of the main unit is so low that the sub-units are too small to be of any practical use and coins of the sub-units are no longer used.Russiawas the first country to convert to a decimal currency when it decimalised under TsarPeter the Greatin 1704, resulting in therublebeing equal to 100 kopeks.

For weights and measures, this is also calledmetrication,replacing traditional units that are related in other ways, such as those formed by successive doubling or halving, or by more arbitraryconversion factors.Units of physical measurement, such as length and mass, were decimalised with the introduction of themetric system,which has been adopted by almost all countries (with the prominent exceptions of theUnited States,and, to a lesser extent, theUnited KingdomandCanada). Thus, a kilometre is 1000 metres, while a mile is 1,760 yards.Electrical unitsare decimalised worldwide. Commonunits of timeremain undecimalised; althoughan attempt was madeduring theFrench Revolution,this proved to be unsuccessful and was quickly abandoned.

Currency decimalisation by region

See also:List of circulating currencies

Decimal currencies have sub-units based on a power of 10. Most sub-units are one-100thof the base currency unit, but currencies based on1,000sub-units also exist in several Arab countries.

Some countries changed the name of the base unit when they decimalised their currency, including:

Examples of currency decimalisation

New unit	=	×	Old unit	Year
German gold mark	=	1⁄3	Vereinsthaler	1873
Danish krone	=	1⁄2	Danish rigsdaler	1875
South African rand	=	1⁄2	South African pound	1961
Australian dollar	=	1⁄2	Australian pound	1966
New Zealand dollar	=	1⁄2	New Zealand pound	1967
Fijian dollar	=	1⁄2	Fijian pound	1969
Nigerian naira	=	1⁄2	Nigerian pound	1973

Europe

In 1534 thekopekofNovgorodwas equated to 1/100 of therubleofMoscow,thus making the Russian ruble Europe's first decimal currency. In the 18th century were introduced the coinsgrivennik(10 kopeks) andimperial(10 rubles). This was not quite decimal currencies as they are known today, as there were smaller units beneath the kopek itself: thedenga(half a kopek, or 200 to the ruble) and thepolushka(half a denga, one-quarter kopek, or 400 to the ruble). After theOctober Revolution,theSoviet Uniontransitioned to a purely decimal model by eliminating the non-decimal subdivisions of the kopek.

Franceintroduced thefrancin 1795 to replace thelivre tournois,abolished during theFrench Revolution.France introduced decimalisation in a number of countries that it invaded during theNapoleonic period.

TheDutch guilderdecimalised in 1817, becoming equal to 100 centen (instead of 20stuivers= 160duiten= 320 penningen), with the last pre-decimal coins withdrawn from circulation in 1848.

Swedenintroduced decimal currency in 1855. Theriksdalerwas divided into 100öre.The riksdaler was renamed thekronain 1873.

TheAustro-Hungarian Empiredecimalised theguldenin 1857, concurrent with its transition from theConventionsthalerto theVereinsthalerstandard.

Spainintroduced its decimal currency unit, thepeseta,in 1868, replacing all previous currencies.

Cyprusdecimalised theCypriot poundin 1955, which comprised 1000 mils, later replaced by 100 cents.

TheUnited Kingdom(including its overseas territories) andIrelanddecimalisedsterlingand theIrish pound,respectively, in 1971. (See£sdandDecimal Day.)

Maltadecimalised thelirain 1972.

The Americas

North America

United States

Decimalisation was introduced into theThirteen Coloniesby theAmerican Revolution,and then enshrined in US law by theCoinage Act of 1792.

Canada

Decimalisation in Canada was complicated by the different jurisdictions before Confederation in 1867. In 1841, the unitedProvince of Canada'sGovernor General,Lord Sydenham,argued for establishment of a bank that would issue dollar currency (theCanadian dollar).Francis Hincks,who would become the Province of Canada's Prime Minister in 1851, favoured the plan. Ultimately the provincial assembly rejected the proposal.In June 1851, the Canadian legislature passed a law requiring provincial accounts to be kept decimalised as dollars and cents. The establishment of acentral bankwas not touched upon in the 1851 legislation. The British government delayed the implementation of the currency change on a technicality, wishing to distinguish the Canadian currency from the United States' currency by referencing the units as "Royals" rather than "Dollars".The British delay was overcome by the Currency Act of 1 August 1854. In 1858, coins denominated in cents and imprinted with "Canada" were issued for the first time.

Decimalisation occurred in:

	Date	Notes
Province of Canada	1 August 1854
Nova Scotia	1 July 1860	Ordered its first coinage in 1860, but the coins were not shipped by the Royal Mint until 1862
New Brunswick	1 November 1860	Like Nova Scotia, the coins were received in 1862
Newfoundland	1866	Took effect in early 1865 and had different coinage from 1865 to 1947
Vancouver Island	1863
British Columbia	1865
Manitoba	1870
Prince Edward Island	1871

The colonial elite, the main advocates of decimalisation, based their case on two main arguments:The first was for facilitation of trade and economic ties with the United States, the colonies' largest trading partner; the second was to simplify calculations and reduce accounting errors.

Mexico

TheMexican pesowas formally decimalised in the 1860s with the introduction of coins denominated in centavos; however, the currency did not fully decimalise in practice immediately and pre-decimal reales were issued until 1897.

Bermuda

Bermuda decimalised in 1970, by introducing theBermudian dollarequal to 8 shillings 4 pence (100 pence, effectively equal to the US dollar under theBretton Woods system).

Caribbean

• TheCuban pesodecimalised in 1869 (became equal to 100 centavos instead of 8 reales).
• TheDominican pesodecimalised in 1877 (became equal to 100 centavos instead of 8 reales).
• TheHaitian gourdedecimalised in 1881 by peg to French franc (became equal to 100 centimes/santim).
• TheNetherlands Antillean guilderdecimalised in 1892 by peg to Dutch guilder (became equal to 100 centen).
• TheBritish West Indies dollardecimalised in 1955.
• TheJamaican dollardecimalised in 1969.

Central America

• Costa Rican pesodecimalised in 1864, divided into 100 centavos, instead of 8 reales.
• Honduran pesodecimalised in 1871, divided into 100 centavos, instead of 8 reales.
• British Honduran (Belize) dollardecimalised in 1885, divided into 100 cents.

South America

• TheVenezuelan pesodecimalised in 1843.
• TheColombian pesodecimalised in 1847 (became equal to 10 décimos instead of 8 reales, later became equal to 100 centavos).
• TheChilean pesodecimalised in 1851 (became equal to 10 décimos or 100 centavos instead of 8 reales).
• TheUruguayan pesodecimalised in 1863.
• ThePeruvian soldecimalised in 1863 (equal to 10 dineros or 100 centavos).
• TheParaguayan pesodecimalised in 1870 (became equal to 100 centésimos, later centavos, instead of 8 reales).
• TheEcuadorian pesodecimalised in 1871.
• TheArgentine pesodecimalised in 1881.

Africa

• TheEthiopian birrdecimalised in 1931 (became equal to 100 metonnyas instead of 16 ghersh).
• TheGhanaian cedidecimalised in 1965.
• TheZambian kwachadecimalised in 1968.
• TheRhodesian dollardecimalised in 1970.
• TheGambian dalasidecimalised in 1971.
• TheMalawian kwachadecimalised in 1971.
• TheNigerian nairadecimalised in 1973.

South Africa

Therandwas introduced on 14 February 1961. A Decimal Coinage Commission had been set up in 1956 to consider a move away from the denominations of pounds, shillings and pence, submitting its recommendation on 8 August 1958.It replaced theSouth African poundas legal tender, at the rate of 2 rand = 1 pound or 10shillingsto the rand. Australia, New Zealand andRhodesiaalso chose ten shillings as the base unit of their new currency.

Oceania

Australia and New Zealand

1964ABCreport describing the design of the soon to be introduced Australian decimal coins

Australiadecimalised on 14 February 1966, with theAustralian dollarsreplacing theAustralian pound.A television campaign containing a memorablejingle,sung to the tune of "Click Go the Shears",was used to help the public to understand the changes.New Zealanddecimalised on 10 July 1967, with theNew Zealand dollarsreplacing theNew Zealand pound.

In both countries, the conversion rate was one pound to two dollars and 10 shillings to one dollar.

Conversion between £sd and $c, Australia and New Zealand

£sd	$c
£50	$100
£10	$20
£5	$10
£1	$2
10/–	$1
5/–	50c
2/–	20c
1/–	10c
6d	5c
3d	2.5c
1.2d	1c
1d	5⁄6c

To ease the transition, the new 5-cent, 10-cent and 20-cents coins were the same size and weight, and the new $1, $2, $10 and $20 banknotes (and the new $100 banknote in New Zealand) were the same colour, as their pre-decimal equivalents. Because of the inexact conversion between cents and pence, people were advised to tender halfpenny, penny and threepence coins in multiples of sixpence (thelowest common multipleof both systems) during the transition.

Rest of Oceania

• Tongan pa'angadecimalised on 3 April 1967
• Samoan taladecimalised on 10 July 1967
• Fijian dollardecimalised on 15 January 1969

Asia

KingChulalongkorndecimalised theThai currencyin 1897. The tical (baht) is now divided into one hundred satang.

Baht	Feuang	Att	Bia	> Decimalization >	Baht	Satang
1	8	64	6400		1	100
1/8	1	8	800
1/64	1/8	1	100
1/6400	1/64	1/100	1

Irandecimalised its currency in 1932, with therial,subdivided into 100 new dinars, replacing theqiranat par.

Saudi Arabiadecimalised theriyalin 1963, with 1 riyal = 100 halalas. Between 1960 and 1963, the riyal was worth 20qirsh,and before that, it was worth 22 qirsh.

TheYemen Arab Republicintroduced the coinage system of 1North Yemeni rial= 100filsin 1974, to replace the 1 rial = 40 buqsha = 80 halala = 160 zalat system. The country was one of the last to convert its coinage.

Japanhistorically had two decimal subdivisions of the yen: the sen (1/100) and the rin (1/1,000). However, they were taken out of circulation as of December 31, 1953, and all transactions are now conducted in multiples of 1 yen.

Rupee-anna-pice-pie to Rupee-paisa conversion

Indiachanged from therupee,anna,piesystem to decimal currency on 1 April 1957.Pakistandecimalisedits currencyin 1961.

In India, Pakistan, and other places under British colonization where a system of 1 rupee = 16anna= 64 pice(old paisa) = 192 pie was used, the decimalisation process defines 1 rupee = 100 naya (new) paisa. The following table shows the conversion of common denominations of coins issued in modern India and Pakistan.

• Bolddenotes the actual denomination written on the coins

Rupee	Anna	Pice	Pie	Paisa/Naya paisa
1⁄192	1⁄12	1⁄3	1 PIE	25⁄48≈ 0.5208
1⁄128	1⁄8	1⁄2PICE	1+1⁄2	25⁄32= 0.78125
1⁄64	1⁄4	1 PICE	3	1+9⁄16= 1.5625
1⁄32	1⁄2ANNA	2	6	3+1⁄8= 3.125
1⁄16	1 ANNA	4	12	6+1⁄4= 6.25
1⁄8	2 ANNAS	8	24	12+1⁄2= 12.5
1⁄4RUPEE	4 ANNAS	16	48	25
1⁄2RUPEE	8 ANNAS	32	96	50
1 RUPEE	16	64	192	100

Burma(nowMyanmar) decimalised in 1952 (predating the Indian case) by changing from therupee(worth 16 pe, each of 4 pyas) to thekyat(worth 100 pyas).

Ceylon(nowSri Lanka) decimalised in 1869, dividing therupeeinto one hundred cents.

Mauritania and Madagascar

MauritaniaandMadagascartheoretically retain currencies with units whose values are in the ratio five to one: theMauritanian ouguiya(MRU) is equivalent to five khoums, and theMalagasy ariary(MGA) to fiveiraimbilanja.

In practice, however, the value of each of these two larger units is very small: as of 2021, the MRU is traded against theeuroat about 44:1, and the MGA at about 4,600:1. In each of these countries, the smaller denomination is no longer used, although in Mauritania there is still a "one-fifth ouguiya" coin.

Non-currency cases

Securities

In the special context of quoting the prices of stocks, traded almost always in blocks of 100 or moresharesand usually in blocks of many thousands, stock exchanges in the United States used eighths or sixteenths of dollars, until converting to decimals between September 2000 and April 2001.

Similarly, in the United Kingdom, the prices of government securities continued to be quoted in multiples of1⁄32of a pound (7+1⁄2d or3+1⁄8p) long after the currency was decimalised.

Metrication

Main article:Metrication

The idea of measurement and currency systems where units are related by factors of ten was suggested bySimon Stevinwho in 1585 first advocated the use of decimal numbers for everyday purposes.TheMetric systemwas developed in France in the 1790s as part of the reforms introduced during theFrench Revolution.Its adoption was gradual, both within France and in other countries, but its use is nearly universal today. One aspect of measurement decimalisation was the introduction ofmetric prefixesto derive bigger and smaller sizes from base unit names. Examples includekilofor 1000,hectofor 100,centifor 1/100 andmillifor 1/1000. The list of metric prefixes has expanded in modern times to encompass a wider range of measurements.

While the commonunits of time,minute, hour, day, month and year, are not decimalised, there have been proposals fordecimalisation of the time of dayanddecimal calendarsystems. Astronomers use a decimalisedJulian day numberto record and predict events. Decades, centuries, andmillenniaare examples of common units of time that are decimalised.Themillisecondis a decimalised unit of time equivalent to a thousandth of a second, and is sometimes used in computing contexts.

Thegradianor grade is anangular unitdefined as one hundredth of theright angle(approximately 0.0157rad), further divided into one hundredcentigrades.

In computer science, there are several metric prefixes used withunits of information.For example, akilobitis equivalent to 1,000bits.

Representing amounts of money

Amounts of money are sometimes described in a decimalised way. For example, the letter K (standing forkilo-) can be used to indicate that a sum of money ought to be multiplied by 1,000 i.e. $250k means $250,000. The letters M or MM can be used to indicate that a sum of money should be multiplied by a million i.e. $3.5M means $3,500,000. The letter B similarly stands for a billion.

See also

• British coinage
• Decimal Day
• Metrication
• Non-decimal currencies

External links

• "Decimal Coinage".Encyclopædia Britannica.Vol. VII (9th ed.). 1878. pp. 20–21.