Americans were at their happiest in the roaring 1920s but at their lowest ebb during the Second World War and the fall of Saigon, a new study that tracked levels of national joy from 1820 has found.
Psychology researchers from Warwick University in the UK used Google books to look at the number of instances of key words signifying happiness and sadness in millions of novels, memoirs and newspapers stretching back to 1825.
They found that happiness reached its peak in the 1920s in America before being sent plunging by the Great Depression.
The outbreak of the Second World War sent happiness levels to an all time low before a brief recovery in the 1950s and 1960s.
But the civil rights struggle and the outbreak of the Vietnam War sent it plunging again.
Spikes in national happiness were sometimes generated by increases in national income but generally it took a very large rise to have any noticeable effect in the US.
In the 1990s Americans saw their happiness soar again as the economy improved, the study says.
National Valence Index plotted from 1820 to 2009. Various important events have been highlighted in red. For all countries the red shaded lines include World War I (approximately 1914-18) and World War II (approximately 1938-45). In the 3 European countries a line is drawn in 1848, the ‘Year of Revolution’. In the USA, there is an additional shaded area representing the Civil War (1861-65) and the vertical red lines representing the Wall Street Crash (1929), the end of the Korean War (1953) and the fall of Saigon (1975). For Germany, the vertical red lines represent the end of Franco-Prussian War and reunification (1870), Hitler’s ascendency to power (1934) and the reunification (1990). In Italy, there is an additional shaded area representing the unification (1861-70)
The research suggests that there is such thing as ‘the good old days’ when people were happier as data consistently showed a higher baseline of happiness from 1825 to the early 1900s – and again in the 1920s.
Information on each nation’s happiness may help governments to make better decisions about policy priorities.
HOW THE STUDY MEASURE HAPPINESS
The study, which is the first of its kind, used innovative methods to build a new index that uses data from books and newspapers to track levels of national happiness between 1820 and 2009.
The main source of language used for the analysis was the Google Books corpus, a collection of word frequency data for over eight million books which makes up more than six per cent of all books ever published.
One theory as to why books and newspaper articles are such a good source of data is that editors prefer to publish pieces which match the mood of their readers.
The method uses psychological valencenorms, or values of happiness that can be derived from text.
This was used for thousands of words in different languages to compute the relative proportion of positive and negative language for four different nations including the UK, USA, Italy and Germany.
Researchers also controlled for the evolution of language, to take into account the fact that some words change their meaning over time.
Dr Chanuki Seresinhe said: ‘It was really important to ensure that the changing meaning of words over time was taken into account. For example, the word ‘gay’ had a completely different meaning in the 1800s than it does today. We processed terabytes of word co-occurrence data from Google Books to understand how the meaning of words has changed over time, and we validate our findings using only words with the most stable historical meanings.’
The study was led by researchers at the University of Warwick, University of Glasgow Adam Smith Business School and The Alan Turing Institute in London.
Commenting on the findings, Professor Thomas Hills told the DailyMail.com: ‘Those changes reflect numerous factors, including standard economics (money in the bank) and the freedom to dissent against foreign wars.
‘The recovery after the war also reflects a potential resiliency in our subjective wellbeing. This is something wellbeing researchers have understood for some time.
‘In many cases our subjective wellbeing is based on comparison with others, but also with recent events, which means it adapts to our circumstances.’
He added: ‘What’s remarkable is that national subjective well-being is incredibly resilient to wars. Even temporary economic booms and busts have little long-term effect.
‘We can see the American Civil War in our data, the revolutions of 48’ across Europe, the roaring 20’s and the Great Depression. But people quickly returned to their previous levels of subjective well-being after these events were over.
‘Our national happiness is like an adjustable spanner that we open and close to calibrate our experiences against our recent past, with little lasting memory for the triumphs and tragedies of our age.’
The US saw its unhappiest time during the second world war, closely followed by the Vietnam war.
Professor Daniel Sgroi said aspirations ‘seem to matter a lot’.
The study found people in the UK were happiest during the interwar years in the 1920s and after the end of the Second World War. The national levels of happiness plunged to its worst in the winter of discontent when union brought the nation to a stand-still.
As recorded by the researchers, the happiness level only reached a comparable level to the inter-war years in the 1990s and pre credit crunch boom years in the early 2000s.
Results could indicate whether current government policies are more or less likely to increase their citizen’s feelings or wellbeing.
Governments the world over are making increasing use of ‘national happiness’ data derived from surveys to help them consider the impact of policy on national wellbeing.
But data for most countries is only available from 2011 onwards and for a select few from the mid 1970s.
This makes it hard to establish long-run trends, or to say anything about the main historical causes of happiness.
In US, happiness reached its peak in the 1920s before Great Depression hit hard. The outbreak of WW2 sent it plunging further before recovery in the 50s and 60s. College-age women line up in Chicago, ca. 1928, pictured
The outbreak of WW2 sent it plunging further before recovery in the 50s and 60s The civil rights struggle and outbreak of the Vietnam War sent it plunging again. Students march with anti-war placards on the campus of the University of California at Berkeley, California in 1969
In order to tackle this problem, the researchers took a key insight from psychology – that more often than not what people say or write reveals much about their underlying happiness level.
They then developed a method to apply it to online texts from millions of books and newspapers published over the past 200 years.
The new index was validated against existing survey-based measures and proven to be an accurate guide to the national mood.
The research was published in the journal Nature Human Behaviour.