Daylight saving time (DST), also known as summer time, is the practice of advancing clocks during part of the year, typically by one hour around spring and summer, so that daylight ends at a later time of the day. As of 2024 [update] , DST is observed in most of Europe, most of North America and parts of Africa and Asia around the Northern Hemisphere summer, and in parts of South America and Oceania around the Southern Hemisphere summer. It was also formerly observed in other areas.
As of November 2024 [update] , the following locations were scheduled to start and end DST at the following times: [1] [2]
Locations | DST start | DST end | Shift | |
---|---|---|---|---|
| Second Sunday in March at 02:00 | First Sunday in November at 02:00 | 1 hour | |
Second Sunday in March at 00:00 | First Sunday in November at 01:00 | 1 hour | ||
| Last Sunday in March at 01:00 UTC | Last Sunday in October at 01:00 UTC | 1 hour | |
Last Sunday in March at 02:00 | Last Sunday in October at 03:00 | 1 hour | ||
Last Sunday in March at 00:00 | Last Sunday in October at 00:00 | 1 hour | ||
Friday before last Sunday in March at 02:00 | Last Sunday in October at 02:00 | 1 hour | ||
Second Saturday after Ramadan [b] at 02:00 | Saturday before last Sunday in October at 02:00 | 1 hour | ||
Last Friday in April at 00:00 | Last Thursday in October at 24:00 | 1 hour | ||
| First Saturday in September at 24:00 UTC−04:00 [c] | First Saturday in April at 24:00 UTC−03:00 [c] | 1 hour | |
First Sunday in October at 02:00 | First Sunday in April at 03:00 | 1 hour | ||
First Sunday in October at 02:00 | First Sunday in April at 02:00 | 30 minutes | ||
Last Sunday in September at 02:00 UTC+12:00 [d] | First Sunday in April at 02:00 UTC+12:00 [d] | 1 hour |
In the table above, the DST start and end times refer to the local time before each change occurs, unless otherwise specified. The shift is the amount of time added at the DST start time and subtracted at the DST end time. For example, in Canada and the United States, when DST starts, the local time changes from 02:00 to 03:00, and when DST ends, the local time changes from 02:00 to 01:00. As the time change depends on the time zone, it does not occur simultaneously in all parts of these countries. Conversely, in almost all parts of Europe that observe DST, the time change occurs simultaneously at 01:00 UTC regardless of their time zone.
Morocco, including the portion of Western Sahara that it administers, also observes an annual time change but not related to seasonal daylight. The local time is decreased by one hour on the Sunday before Ramadan at 03:00, and increased by one hour on the Sunday after Ramadan at 02:00 (in 2024, the dates are 10 March and 14 April).
Location | Last year of time changes [e] | Notes [1] |
---|---|---|
Akrotiri and Dhekelia | Observed DST since 1939. | |
Albania | Observed DST in 1940–1943, and since 1974. | |
Algeria | 1981 | Observed DST in 1916–1921, in the autumn of 1939, in 1944–1945, 1971, 1977–1978, and 1980–1981. |
Andorra | Observed DST since 1985. | |
Argentina | 2009 | Observed DST in 1930–1969, 1974, 1988–2000, and 2007–2009. |
Armenia | 2011 | Observed DST in 1981–1995, 1997–2011. [7] |
Australia | Australian Capital Territory, Jervis Bay Territory, New South Wales, Norfolk Island, South Australia, Tasmania, and Victoria. | DST used only in the|
Austria | Observed DST in 1916–1918, 1920, 1940–1948 (as part of Germany between 1940 and 1945) and since 1980. | |
Azerbaijan | 2015 | Observed DST in 1981–1992 and 1996–2015. |
Bahamas | Observed DST since 1964. | |
Bangladesh | 2009 | Observed DST during World War II from 1942 to 1945 as a part of the Bengal Presidency of India. Also observed in 2009. |
Barbados | 1980 | Observed DST from 1977 to 1980. |
Belarus | 2010 | Observed DST in 1941–1944, 1981–2010. |
Belgium | Observed DST in 1916–1940, 1942–1946 and since 1977. | |
Belize | 1983 | Observed DST in 1973–1974 and 1982–1983. |
Bermuda | Observed DST since 1974. | |
Bolivia | 1932 | Observed DST in 1931–1932. |
Bosnia and Herzegovina | Observed DST in 1916–1918 when it was part of Austria-Hungary, in 1941–1945 and since 1983 when it was part of Yugoslavia or independent. | |
Botswana | 1944 | Observed DST in 1943–1944. |
Brazil | 2019 | Observed DST in 1931–1933, 1949–1953, 1963–1968, and 1985–2019. |
Bulgaria | Observed DST in 1943–1944 and since 1979. | |
Canada | Yukon, most of Saskatchewan, and parts of British Columbia, Nunavut, Ontario and Quebec do not observe DST. Yukon and most of Saskatchewan use time zones equivalent to permanent DST. [8] | |
Cape Verde | 1945 | Observed DST in 1942–1945. |
Chad | 1980 | Observed DST in winter 1979–1980. |
Chile | Observed DST in 1927–1946 (excluding Easter Island, which observed it in 1932–1946) and from 1968 to 2015. Chile observed year-round DST in 2015, but reintroduced regular DST in 2016. Magallanes Region does not observe DST since December 2016. | |
China | 1991 | Observed DST in 1940–1941 (when it was Republic of China) and 1986–1991. |
Colombia | 1993 | Observed DST in 1992–1993. |
Cook Islands | 1991 | Observed DST in 1978–1991. |
Costa Rica | 1992 | Observed DST in 1954, 1979–1980 and 1991–1992. |
Croatia | Observed DST in 1916–1918 when it was part of Austria-Hungary, in 1941–1945 and since 1983 when it was part of Yugoslavia or independent. | |
Cuba | Observed DST in 1928, 1940–1942, 1945–1946, and since 1965. | |
Cyprus | Observed DST since 1975. | |
Czech Republic | Observed DST in 1916–1918 when it was part of Austria-Hungary, 1940–1949 and since 1979 when it was part of Czechoslovakia or independent. | |
Denmark | Observed DST in 1916, 1940–1948, and since 1980. | |
Dominican Republic | 1974 | Observed DST in 1966–1967, 1969–1974. |
Egypt | Observed DST in 1940–1945, 1957–2010, 2014, and since 2023. | |
El Salvador | 1988 | Observed DST in 1987–1988. |
Estonia | Observed DST in 1918, 1940–1944, 1981–1988, 1997–1999, and since 2002. | |
Faroe Islands | Observed DST since 1981. | |
Falkland Islands | 2010 | Observed DST in 1937–1942 and 1983–2010. |
Fiji | 2021 | Observed DST in 1998–2000 and 2009–2021. |
Finland | Observed DST in 1942 and since 1981. | |
France | Observed DST in 1916–1945 and since 1976. | |
Georgia | 2005 | Observed DST in 1981–2005. |
Germany | Observed DST in 1916–1918, 1940–1949, and since 1980. | |
Ghana | 1942 | Observed DST in 1936–1942. |
Greece | Observed DST in 1932–1952 and since 1975. | |
Greenland | Observed DST since 1980. Follows European Union practice as part of the Kingdom of Denmark, hence start and end times correspond to 01:00 UTC on the respective Sunday. See Daylight saving time in the Americas—Greenland. The Pituffik Space Base uses the DST schedule of Canada and the United States. Stations on the east coast of Northeast Greenland National Park do not observe DST. [f] | |
Guatemala | 2006 | Observed DST in 1973–1974, 1983, 1991, and 2006. |
Guernsey | Observed DST in 1916–1968 and since 1972. | |
Haiti | Observed DST in 1983–1997, 2005–2006, 2012–2015, and since 2017. | |
Honduras | 2006 | Observed DST in 1987–1988 and 2006. |
Hong Kong | 1979 | Observed DST in 1941, 1945–1976, and 1979. |
Hungary | Observed DST in 1916–1920, 1941–1950, 1954–1957, and since 1980. | |
Iceland | 1968 | Observed DST in 1917–1918 and 1939–1968. |
India | 1945 | Observed DST during World War II from 1941 to 1945. Briefly observed during the Sino-Indian War of 1962 and the Indo–Pakistani Wars of 1965 and 1971. |
Indonesia | 1963 | Observed various DST offsets in 1924–1963. |
Iraq | 2007 | Observed DST in 1982–2007. |
Iran | 2022 | Observed DST in 1977–1980, 1991–2005, and 2008–2022. |
Ireland | Observed DST in 1916–1968 and since 1972. | |
Isle of Man | Observed DST in 1916–1968 and since 1972. | |
Israel | Observed DST in 1940–1946, 1948–1957, 1974–1975, 1980, and since 1984. | |
Italy | Observed DST in 1916–1920, 1940–1948, and since 1966. | |
Jamaica | 1983 | Observed DST in 1974–1983. |
Japan | 1951 | Observed DST in 1948–1951. |
Jersey | Observed DST in 1916–1968 and since 1971. | |
Jordan | 2022 | Observed DST with annual time changes in 1973–1978 and 1985–2011, permanently in 2012–2013, with annual time changes in 2014–2022, and permanently since 2022. |
Kazakhstan | 2004 | Observed DST in 1981–1990 and 1992–2004. |
Kosovo | Observed DST 1941–1945 and since 1983 when it was part of Yugoslavia, Serbia and Montenegro, Serbia or independent. | |
Kyrgyzstan | 2005 | Observed DST in 1981–2005. |
Latvia | Observed DST in 1918–1919, 1941–1944, and since 1981. | |
Lebanon | Observed DST in 1920–1923, 1957–1961, 1972–1978, and since 1984. | |
Lesotho | 1944 | Observed DST in 1943–1944. |
Libya | 2013 | Observed DST in 1951–1959, 1982–1989, 1996–1997, and 2012–2013. |
Liechtenstein | Observed DST since 1981. | |
Lithuania | Observed DST in 1941–1944, 1981–1999, and since 2003. | |
Luxembourg | Observed DST in 1916–1946 and since 1977. | |
Macau | 1979 | Observed DST in 1941–1943, 1945–1976 and 1979. |
Madagascar | 1954 | Observed DST in 1954. |
Malaysia | 1936 | Observed DST in 1933–1936. The time zone in Malaysia also changed many times in the past. |
Malta | Observed DST in 1916–1920, 1940–1948, and since 1966. | |
Martinique | 1980 | Observed DST in 1980. |
Mauritius | 2009 | Observed DST in 1982–1983 and 2008–2009. |
Mexico | Baja California started observing DST in 1976. Durango, Coahuila, Nuevo León and Tamaulipas observed DST in 1988. The whole country started observing DST in 1996, but Sonora discontinued the observance after 1998, Quintana Roo after 2014, and the rest of the country after 2022, except Baja California and municipalities near the U.S. border in Chihuahua, Coahuila, Nuevo León and Tamaulipas, which continued observing DST according to the U.S. schedule. | |
Midway Atoll | 1956 | Observed DST in 1956. |
Moldova | Observed DST in 1932–1944, 1981–1989, and since 1991. | |
Monaco | Observed DST in 1916–1945 and since 1976. | |
Mongolia | 2016 | Observed DST in 1983–1998, 2001–2006, and 2015–2016. |
Montenegro | Observed DST 1941–1945 and since 1983 when it was part of Yugoslavia, Serbia and Montenegro or independent. | |
Morocco | 2018 | Observed DST in 1939–1945, 1950, 1967, 1974, 1976–1978, and 2008–2018. In 2012–2018, DST was suspended during the month of Ramadan. Since 2018 Morocco uses UTC+1 all year, equivalent to permanent DST, except during the month of Ramadan, when it observes UTC±0. |
Namibia | 2017 | Adopted standard time of UTC+2 in 1903. Observed annual changes to summer time in 1942–1943 (UTC+3 summer, UTC+2 standard). Observed annual changes to winter time in 1994–2017 (UTC+2 standard, UTC+1 winter) in all regions except Zambezi, which remained in UTC+2 all year. [10] |
Netherlands | Observed DST in 1916–1945 and since 1977. | |
New Caledonia | 1997 | Observed DST in 1977–1979 and 1996–1997. |
New Zealand | Observed DST in 1927–1946 and since 1974. | |
Nicaragua | 2006 | Observed DST in 1973–1975, 1979–1980, 1992–1994, and 2005–2006. |
Norfolk Island | Observed DST in 1974–1975 and since 2019. [11] | |
North Macedonia | Observed DST in 1941–1945 and since 1983 when it was part of Yugoslavia or independent. | |
Northern Cyprus | Observed DST since 2017. Maintained permanent DST from September 2016 to October 2017. [12] | |
Norway | Observed DST in 1916, 1940–1945, 1959–1965, and since 1980. Follows European Union practice, although not a member. | |
Pakistan | 2009 | Observed DST in 1942–1945 as a part of the British Raj. Also observed in 2002 and from 2008 to 2009. |
Palestine | Since 1974, observed DST in the same years when Israel did, but not always with the same start and end dates. | |
Paraguay | 2024 | Observed DST in 1975–2024. In October 2024 adopted UTC–3, equivalent to permanent DST. [13] |
Peru | 1994 | Observed DST in 1938–1940, 1986–1987, 1990, and 1994. |
Philippines | 1990 | Observed DST in 1936–1937, 1954, 1978, and 1990. |
Poland | Observed DST in 1916–1919, 1940–1949, 1957–1964, and since 1977. | |
Portugal | Observed DST in 1916–1921, 1924, 1926–1929, 1931–1932, 1934–1949, 1951–1965, and since 1977. | |
Puerto Rico | 1945 | Observed DST in 1942–1945. |
Romania | First time when DST was observed in Romania was in 1917, due to World War I. Observed DST in 1932–1939 and since 1979. | |
Russia | 2014 | Observed DST in 1917–1919, 1921 (some areas), and 1981–2010. In 2011–2014, used permanent DST. In 2014, left permanent DST and switched to permanent standard time. [14] |
Saint Pierre and Miquelon | Observed DST since 1987. | |
Samoa | 2021 | Observed DST in 2010–2021. |
San Marino | Observed DST in 1916–1920, 1940–1948, and since 1966. | |
Serbia | Observed DST in 1941–1945 and since 1983 when it was part of Yugoslavia, Serbia and Montenegro or independent. [15] | |
Sierra Leone | 1962 | Observed DST in 1935–1942 and 1957–1962. |
Singapore | 1935 | Observed DST in 1933–1935 by adding 20 minutes to standard time. On January 1, 1936, country changed their time zone to UTC+07:20. [16] |
Slovakia | Observed DST in 1916–1918 when it was part of Austria-Hungary, 1940–1949 and since 1979 when it was part of Czechoslovakia or independent. | |
Slovenia | Observed DST in 1916–1918 when it was part of Austria-Hungary, in 1941–1945 and since 1983 when it was part of Yugoslavia or independent. | |
South Africa | 1944 | Observed DST in 1942–1944. |
South Korea | 1988 | Observed DST in 1948–1951, 1955–1960, and 1987–1988. |
South Sudan | 1985 | Observed DST in 1970–1985, when it was part of Sudan. |
Spain | Observed DST in 1917–1919, 1924, 1926–1929, 1937–1946, 1949, and since 1974. The Canary Islands observed DST since 1980. | |
Sri Lanka | 2006 | Observed DST during the World War II, from 1942 to 1945 just as the rest of the Indian subcontinent. Advanced one hour to UTC+6:30 in May 1996, reduced 30 minutes to UTC+6 in October 1996, and reduced 30 minutes to UTC+5:30 in April 2006. |
Sudan | 1985 | Observed DST in 1970–1985. |
Sweden | Observed DST 15 May–30 September 1916, in a test run. Observed DST since 1980. Dates: 1980, first Sunday of April to last Sunday of September; 1981–1995, last Sunday of March to last Sunday of September; since 1996, last Sunday of March to last Sunday of October. | |
Switzerland | Observed DST in 1941–1942 and since 1981. Follows European Union practice, although not a member. | |
Syria | 2022 | Observed DST in 1920–1923, 1962–1978, 1983–1984, and 1986–2022. In 2022 switched to UTC+03:00, equivalent to permanent DST. |
Taiwan | 1979 | Observed DST in 1945–1962, 1974, 1975, and 1979. |
Tajikistan | 1991 | Observed DST in 1981–1991. |
Tonga | 2017 | Observed DST in 1999–2002 and 2016–2017. |
Tunisia | 2008 | Observed DST in 1939–1945, 1977–1978, 1988–1990, and 2005–2008. |
Turkey | 2016 | Turkey Time time zone (UTC+03:00), moving in effect to permanent DST. | Observed DST in 1916, 1920–1922, 1924–1925, 1940–1942, 1945–1951, 1962, 1964, 1970–1983, and 1985–2016. Followed European Union practice in general. In 2016, Turkey adopted the new
Turkmenistan | 1991 | Observed DST in 1981–1991. |
Turks and Caicos | Observed DST in 1979–2015 and since 2018. | |
Ukraine | Observed DST in 1941–1943, 1981–1989, and since 1992. Follows European Union practice, although not a member. Since 2014, occupied territories of Ukraine do not de facto observe DST. | |
United Kingdom | Summer Time (BST) + Double Summer Time (BDST) 1940–1945. Two-stage Double Summer Time (BDST) 1947. Year-round Summer Time (BST) 1968–1971. Follows European Union practice, although no longer a member. | Observed DST (commonly referred to as British Summer Time (BST)) since 1916. Year-round|
United States | Arizona (except the Navajo Nation) and Hawaii do not observe DST. [8] Year-round DST observed in 1942–1945 and 1974–1975. | |
Uruguay | 2015 | Observed DST in 1923–1926, 1933–1943, 1959–1960, 1965–1970, 1972, 1974–1980, 1987–1993, and 2004–2015. [17] |
Uzbekistan | 1991 | Observed DST in 1981–1991. |
Vanuatu | 1993 | Observed DST in 1983–1993. |
Vatican City | Observed DST in 1916–1920, 1940–1948, and since 1966. | |
Western Sahara | 2018 | The portion administered by Morocco since 1976 observed DST whenever the country did. |
Many countries and territories have abolished annual time changes after observing them for many years: Argentina, Armenia, Azerbaijan, Belarus, Brazil, Cook Islands, Falkland Islands, Fiji, Georgia, Hong Kong, Iceland, Iran, Iraq, Jamaica, Jordan, Kazakhstan, Kyrgyzstan, Macau, Mongolia, Namibia, Paraguay, Russia, Samoa, Sudan, Syria, Turkey, Uruguay, Vanuatu, and most of Mexico. To select the time to be used all year, some of them adopted the time previously used outside their DST period, but others adopted the time previously used during their DST period, an effect known as "permanent DST".
On 8 February 2018, the European Parliament voted to ask the European Commission to re-evaluate DST in the European Union. [18] An online survey was performed between 4 July and 16 August 2018, in which 4.6 million EU citizens [19] responded. The survey was especially popular in Germany, resulting in 68% of all respondents located in that country. [20] Out of all the participants, about 84% did not desire to adjust clocks twice annually. [19] Based on this poll, on 12 September 2018 the European Commission decided to propose an end to seasonal clock changes (repealing Directive 2000/84/EC). [21] In order for this proposal to be valid, the European Union legislative procedure must be followed, mainly that the Council of the European Union and the European Parliament must both approve it.
The seasonal changes were supposed to stop in 2021, but the Council of the European Union asked the European Commission for a detailed impact assessment before countries would decide on how to proceed. [20]
Since 2018, several U.S. states have passed laws to abolish seasonal changes and adopt permanent DST, but these laws cannot take effect without approval from the federal government. [22] States may freely choose whether to observe DST or not, but if they observe it they must follow the national schedule, and changing their standard time also requires approval from the federal government.
The Sunshine Protection Act would change federal law to abolish annual time changes and permanently advance by one hour the standard time in all areas of the United States that previously observed DST, effectively adopting permanent DST, from 2023. The proposal passed the Senate with unanimous consent on March 15, 2022, but expired without consideration by the House of Representatives. [23]
A time zone is an area which observes a uniform standard time for legal, commercial and social purposes. Time zones tend to follow the boundaries between countries and their subdivisions instead of strictly following longitude, because it is convenient for areas in frequent communication to keep the same time.
Daylight saving time (DST), also referred to as daylight saving(s), daylight savings time, daylight time (United States and Canada), or summer time (United Kingdom, European Union, and others), is the practice of advancing clocks to make better use of the longer daylight available during summer so that darkness falls at a later clock time. The typical implementation of DST is to set clocks forward by one hour in spring or late winter, and to set clocks back by one hour to standard time in the autumn (or fall in North American English, hence the mnemonic: "spring forward and fall back").
Central European Time (CET) is a standard time of Central, and parts of Western Europe, which is one hour ahead of Coordinated Universal Time (UTC). The time offset from UTC can be written as UTC+01:00. It is used in most parts of Europe and in a few North African countries. CET is also known as Middle European Time and by colloquial names such as Amsterdam Time, Berlin Time, Brussels Time, Budapest Time, Madrid Time, Paris Time, Rome Time, Prague time, Warsaw Time or Romance Standard Time (RST).
Western European Time is a time zone covering parts of western Europe and consists of countries using UTC+00:00. It is one of the three standard time zones in the European Union along with Central European Time and Eastern European Time.
Summer time in Europe is the variation of standard clock time that is applied in most European countries in the period between spring and autumn, during which clocks are advanced by one hour from the time observed in the rest of the year, with a view to making the most efficient use of seasonal daylight. It corresponds to the notion and practice of daylight saving time (DST) to be found in some other parts of the world.
Eastern European Time (EET) is one of the names of UTC+02:00 time zone, 2 hours ahead of Coordinated Universal Time. The zone uses daylight saving time, so that it uses UTC+03:00 during the summer.
The Atlantic Time Zone is a geographical region that keeps standard time—called Atlantic Standard Time (AST)—by subtracting four hours from Coordinated Universal Time (UTC), resulting in UTC−04:00. AST is observed in parts of North America including several Caribbean islands. During part of the year, some portions of the zone observe daylight saving time, referred to as Atlantic Daylight Time (ADT), by moving their clocks forward one hour to UTC−03:00. The clock time in this zone is based on the mean solar time of the 60th meridian west of the Greenwich Observatory.
Moscow Time is the time zone for the city of Moscow, Russia, and most of western Russia, including Saint Petersburg. It is the second-westernmost of the eleven time zones of Russia. It has been set to UTC+03:00 without DST since 26 October 2014; before that date it had been set to UTC+04:00 year-round on 27 March 2011.
UTC+03:00 is an identifier for a time offset from UTC of +03:00. In areas using this time offset, the time is three hours ahead of the Coordinated Universal Time (UTC). Following the ISO 8601 standard, a time with this offset would be written as, for example, 2019-02-08T23:36:06+03:00.
There are 11 time zones in Russia, which currently observe times ranging from UTC+02:00 to UTC+12:00. Daylight saving time (DST) has not been used in Russia since 26 October 2014. From 27 March 2011 to 26 October 2014, permanent DST was used.
Canada is divided into six time zones. Most areas of the country's provinces and territories operate on standard time from the first Sunday in November to the second Sunday in March and daylight saving time the rest of the year.
Time in Chile is divided into three time zones. Most of Continental Chile uses the time offset UTC−04:00 in winter time and UTC−03:00 in summer time, while the Magallanes and Chilean Antarctica region uses the time offset UTC−03:00 the whole year. Additionally, Easter Island uses the time offset UTC−06:00 in winter time and UTC−05:00 in summer time.
Iran Standard Time (IRST) or Iran Time (IT) is the time zone used in Iran. Iran uses a UTC offset UTC+03:30. IRST is defined by the 52.5 degrees east meridian, the same meridian which defines the Iranian calendar and is the official meridian of Iran.
UTC+00:00 is an identifier for a time offset from UTC of +00:00. This time zone is the basis of Coordinated Universal Time (UTC) and all other time zones are based on it. In ISO 8601, an example of the associated time would be written as 2069-01-01T12:12:34+00:00. It is also known by the following geographical or historical names:
Europe spans seven primary time zones, excluding summer time offsets. Most European countries use summer time and harmonise their summer time adjustments; see Summer time in Europe for details.
Ireland uses Irish Standard Time in the summer months and Greenwich Mean Time in the winter period.
Daylight saving time in the Americas is the arrangement in the Americas by which clocks are advanced by one hour in spring and moved back in autumn, to make the most of seasonal daylight. The practice is widespread in North America, with most of Canada and the United States participating, but much less so in Central and South America.
As of 2018, daylight saving time (DST) is permanently observed in Morocco. Previously, time was advanced to UTC+01:00 at 02:00 on the last Sunday of March, and reverted to UTC+00:00, defined as Greenwich Mean Time locally, at 03:00 on the last Sunday of October. This practice was continued until October 2018, after which clocks were permanently advanced. An exception was made during the month of Ramadan during which clocks reverted to UTC+00:00.
As of 2022, daylight saving time is used in the following Asian countries:
Denmark, including its dependencies of Faroe Islands and Greenland, uses six time zones.