A bellwether is one that leads or indicates trends; a trendsetter.
The term is derived from the Middle English bellewether and refers to the practice of placing a bell around the neck of a castrated ram (a wether) leading his flock of sheep. The movements of the flock could be noted by hearing the bell before the flock was in sight.
In politics, the term is more often applied in the passive sense to describe a geographic region where political tendencies match in microcosm those of a wider area, such that the result of an election in the former region might predict the eventual result in the latter. In a Westminster-style election, for example, a constituency, the control of which tends frequently to change, can mirror in its popular vote the result on a national scale.
In Australian federal elections, the electoral division of Eden-Monaro in New South Wales elected its Member of Parliament from the party which won government at every federal election from 1972 until 2016, when the record was broken after Labor won the seat, while the Coalition won government. Following this, the Division of Robertson in NSW became the nation's new longest-running bellwether seat, continually won by party that also won government since the 1983 election. The Division of Lindsay in NSW, has elected its Member of Parliament from the party which won government in every Federal election since its creation in 1984. Both Lindsay and Eden-Monaro lost their bellwether status in the 2016 election, both electing Labor MPs, despite a narrow Coalition win nationwide. The Division of Makin in South Australia was a bellwether division from 1984 until 2010, although ceased its bellwether record in 2013, when Makin stayed Labor as the Coalition regained power nationwide. Also, in terms of nationwide two party preferred vote, Eden-Monaro, Lindsay, Robertson and Makin have bucked the bellwether trend in the past by voting Liberal at the 1998 federal election. In purely statistical terms, the state of New South Wales, which has the largest population of any Australian state or territory, could also be considered a "bellwether", as, until the 2016 federal election the party which wins government has won the majority of House of Representatives seats in that state at every election since 1963. Unlike many bellwethers, these are cited by analysts solely for their record and are not usually attributed to demographic factors that reflect the median of Australia.
In Brazilian direct presidential elections, the states of Bahia and Rio Grande do Norte is where the winning candidate took the lead in the last-round election from 1945 to 2014. Tocantins, since its creation in 1988, always had the winning presidential candidate winning the state lead in votes.
In the Canadian province of Ontario, Sarnia-Lambton (and its predecessor ridings) voted for the winning party in every federal election from 1963 until 2011. This streak was broken in 2015. St. Paul's has only elected three opposition MPs since it was created in 1935. Also in Ontario, Peterborough has been won by the party who has won the most seats overall in provincial elections since 1977. In Alberta, Peace River has elected only three opposition MLAs since the province was founded in 1905.
Since the fifth republic president was elected by popular vote in 1965 up to 2012, five departments have always voted the chosen candidate in the second round: Ardeche, Calvados, Charente-Maritime, Indre-et-Loire and Loire. No region has done so.
Since the creation of the Federal Republic of Germany (then West Germany) in 1949, the state where the leading party list vote (Zweitstimmen) matched the party of the subsequently chosen Chancellor more times is Schleswig-Holstein (with two misses: 1969 and 2005), followed by the state of Lower Saxony (with misses in 1949, 1969 and 2005). Both states lie in the North of the country, neither containing many large industrial cities (the biggest being Kiel and Hannover respectively), nor large rural catholic populations, the traditional base of SPD and CDU/CSU respectively. Schleswig Holstein is also famous for having had several state elections result in a one-seat majority for the winning coalition and Lower Saxony's 1998 election (in which Gerhard Schröder was the SPD candidate) is often seen as a "trial run" for the subsequent federal election (which Schröder also won). Both the 1949 and the 1969 elections were rather narrow, the former resulting in a one-vote majority in the election for chancellor and the latter resulting in a 12-seat majority that had broken down due to defections by 1972.
Ireland has a proportional representation electoral system, in which politicians are elected by the single transferable vote. Bellwethers here can only be measured by the number of candidates from each side elected to Ireland's multiple-seat constituencies that elect an odd number of members. Between the 1981 general election and 2011 general election, Meath and its successors, Meath East and Meath West, have elected a majority of Fianna Fáil TDs in years when Fianna Fáil formed the government, and a majority of Fine Gael and Labour TDs when those parties formed the government.
In New Zealand, there are three generally accepted bellwether electorates: Hamilton East and Hamilton West, both based around the city of Hamilton, and Northcote on Auckland's North Shore. Hamilton West and Northcote have only missed one election each since they were first contested in 1969 and 1996 respectively — the 1993 election for Hamilton West and the 2005 election for Northcote. Hamilton East, first contested in 1972, has missed three elections — 1993, 1999, and 2005.
In the Philippines, the winner of Philippine presidential election has won in Negros Oriental in all instances since 1935 except for 1961 and 2016, and in Basilan since its creation in December 1973. After Negros Oriental voted for the runner-up in 2016, Basilan's streak that started in 1978 is currently the nation's longest.
For vice presidential elections, Pangasinan has voted for the winner in all elections save for 1986 and 2016.
In every general election to the National Assembly since the restoration of democracy the electoral district of Braga has voted for the party or coalition that has won the most seats in the election. (Note that following the elections of 2015, a minority government was eventually formed by the second-largest party in the Assembly.)
Since democracy was restored in 1977 up to 2015 elections, three provinces have always voted for the winning party (Teruel, Zaragoza and Huesca), as has the Autonomous Community of Aragon, where said provinces are located. Aragon is, moreover, the sole Autonomous Community to have done so.
According to Statistics Sweden, election results in Karlstad have been closest to the national results for three consecutive elections, a fact often highlighted by media through Gallup Polls showing voting intentions in the area.
United Kingdom constituencies have been subject to frequent review since the late 1960s, particularly those of the House of Commons. Few constituencies are unchanged from one review to another. Therefore, true bellwethers are rare. However, it is possible to match new constituencies to old ones according to the destination of the bulk of the old electorate.
Long running bellwether constituencies
- The Dartford constituency has reflected the overall result in every General Election since 1964
- The Basildon constituency has reflected every result since 1974
- The Loughborough constituency has reflected every result since the February 1974 election
- The Bristol North West constituency has reflected every result since the October 1974 election
- The Reading West and Amber Valley constituencies have reflected every result since 1983
- The Battersea constituency has reflected every result since 1987
Former bellwether constituencies
- The Gravesham constituency (and its predecessor Gravesend) had reflected the overall result from 1918 until 2005
- The Luton South constituency (and its predecessors Luton East and Luton) had reflected the overall result an MP from 1951 until 2010.
The constituencies of Cunninghame North, Stirling and Na h-Eileanan an Iar have all elected MSPs from the party which won the plurality of seats in the election overall for every Scottish Parliament election.
Also, the constituencies of Almond Valley, Dundee City West, Edinburgh Eastern,, Glasgow Southside, Kilmarnock and Irvine Valley and Mid Fife and Glenrothes each elected an MSP from the largest party in the 2011 and 2016 elections. This continues the trend that their predecessor constituencies (Livingston, Dundee West, Edinburgh East & Musselburgh, Glasgow Govan, Kilmarnock & Loudoun and Fife Central) achieved in the 1999, 2003 and 2007 elections.
The American bellwether states can be determined in different ways (with respect to presidential elections):
Highest percentage for varying lengths of time
- Ohio – 2 misses (1944, 1960) from 1896 on (93.6%, slightly "too Republican"). Currently the longest perfect streak.
- Florida – 2 misses (1960, 1992) from 1928 on (91.3%, slightly "too Republican").
- Nevada – 2 misses (1976, 2016) from 1908 on (92.9%, "neutral").
- New Mexico – 3 misses (1976, 2000, 2016) from 1912 on (88.9%, slightly "too Democratic"). The state of New Mexico voted for the winner of the popular vote in 2000 and 2016.
- Missouri – 3 misses (1956, 2008, 2012) from 1904 on (89.7%, slightly "too Republican"). Was often referred to as the "Missouri bellwether" until 2012, when it voted for Mitt Romney. Donald Trump won Missouri in 2016 by as many as 19 points, which suggests it will likely be less of a bellwether state in future elections.
Highest percentage for a set length of time
Electoral record of the states for presidential elections, 1896–2012
- Ohio : 28 wins out of 30 elections 93%
- New Mexico : 24 wins out of 26 elections 92%
- Illinois : 26 wins out of 30 elections 87%
- Nevada : 26 wins out of 30 elections 87%
Smallest deviation from the national average
Another way to measure how much a state's results reflect the national average is how far the state deviates from the national results. The states with the least deviation from a two-party presidential vote from 1896 to 2012 include:
States that were considered bellwether states from the mid-to-late 20th century until the early 21st century include
- Delaware – Perfect from 1952 to 1996, the only state with this distinction. As a result of massive growth and a move to the Democrats in New Castle County, Delaware (suburban Philadelphia, with the old industrial city of Wilmington), the state has become reliably Democratic.
- Illinois – 3 misses (1884, 1916, 1976) from 1852 to 1996, the most reliable in this period. As the Chicago metropolitan area shifted to become overwhelmingly Democratic, the state lost its bellwether status.
- Missouri was often referred to as the Missouri bellwether as it produced the same outcome as the national results in the presidential election 96.2% of the time for the century between 1904 and 2004, only missing in 1956. It did not match the national result in 2008 or 2012, and is considered to have lost its bellwether status.
In addition, the Territory of Guam has had no misses from 1984 on (100.0%). Guam has no electoral college votes, but conducts a straw vote on local election day. Also of note, from 1996 through 2012, Ohio has been within 1.85% of the national popular vote result. Due to the Electoral College system, a bellwether of sufficient size is often also a focus of national attention and presidential campaigns as a so-called swing state that can decide the election one way or the other. As of 2016, Ohio and Florida are seen as the most important swing states and no Republican has won the presidency while losing Ohio and the controversial decision in Bush v. Gore ultimately hinged on a recount of Florida, that – had it gone for Gore – would have swung the Electoral College vote.
American bellwether counties include:
- Vigo County, Indiana (county seat: Terre Haute) – 2 misses (1908, 1952) from 1888 on, perfect since 1956. From 1960 to 2004, Vigo County had been within 3 percent of the national presidential vote every election. In 2008, Vigo County again voted with the winner, but Obama's percentage of 57.3% was about 4.4% above Obama's national vote. In 2012, Vigo kept its streak going, voting for President Obama, 49.5% to Romney's 48.6%. Vigo County also rightfully predicted Trump's landslide victory in 2016.
- Ottawa County, Ohio (county seat: Port Clinton) – perfect since 1964.
- Bexar County, Texas (county seat: San Antonio) – Two misses since 1928 (in 1968 and 2016).
- Hidalgo County, New Mexico (county seat: Lordsburg) – one miss since 1928 (in 1968).
- Valencia County, New Mexico – perfect since 1952.
- Wood County, Ohio (county seat: Bowling Green) – one miss since 1964 (in 1976).
- Stanislaus County, California (county seat Modesto) – perfect since 1972.
- Ventura County, California – two misses since 1920 (in 1976 and 2016).
- Merced County, California (county seat Merced) – one miss since 1972 [in 2016].
- Hillsborough County, Florida (county seat: Tampa) – two misses since 1928 (in 1992 and 2016). Although its history as a bellwether is shorter than others, the fact that the county is in a swing state and recent demographic changes strengthen its importance.
In the stock market, a bellwether (barometer stock in the UK) is a stock that is believed to be a leading indicator of the direction of a sector, industry or market as a whole. Bellwether stocks are often used to determine the direction in which an industry or market is headed in the short term. JPMorgan Chase is an example of a bellwether stock. As one of the major banks in the United States, it sets the tone for the rest of the industry. JPMorgan Chase also has contracts with companies in other industries, so its performance is reflected in other sectors of the market. Cognizant is similarly a bellwether for Technology stocks in the Indian markets BSE and NSE.
Trends in expenditure in the UK advertising and marketing industry are monitored in the quarterly Bellwether Report, published by the Institute of Practitioners in Advertising (IPA).