The prize in economics was developed by Sweden's central bank in memory of Alfred Nobel.
The 2021 Nobel Prize in Economics was awarded on Monday to three economists who used natural experiments -- those arising in real life -- and showed that they "can be used to answer central questions for society."
David Card, Joshua Angrist and Guido Imbens will share the award, the Royal Swedish Academy of Sciences announced in Stockholm.
Card, at the University of California, Berkeley, was given half of the award for analysing "the labour market effects of minimum wages, immigration and education".
Angrist and Dutch-born Imbens received the other half of the award for "demonstrating how precise conclusions about cause and effect can be drawn from natural experiments".
The award is worth 10 million Swedish kronor, which is roughly €988,000.
The academy said that the three economists had "revolutionised empirical research in the economic sciences."
Imbens said at the press conference that he was "just absolutely stunned" when he received the call and was "thrilled to hear the news" and share it with his friends, Card and Angrist.
Last year's economics prize went to two American economics from Stanford University, Paul Milgrom and Robert Wilson, who figured out how to make auctions work more efficiently.
This prize, always the last to be awarded of the six, was established by Sweden's central bank (Sveriges Riksbank) in memory of the Nobel prize founder Alfred Nobel. The first prize was awarded in 1969.
Some had speculated that the prize could be awarded to a woman as only two women have received the economics award out of the 89 laureates. Only one woman received a Nobel award out of the six prizes given this year.
The Stanford economists who won last year shared a video of Milgrom finding out about the win when his colleague and neighbour knocked on his door in the middle of the night to share the news.
Who were the other Nobel Prize winners this year?
Five Nobel Prizes were awarded last week, including the Nobel Peace Prize which was given on Friday to two journalists, Maria Ressa and Dmitry Muratov, who created independent news in the Philippines and Russia.
The Nobel Prize in physiology or medicine was awarded on Monday to David Julius and Ardem Patapoutia for discoveries related to how humans sense heat, cold and touch.
Three scientists, Syukuro Manabe, Klaus Hasselmann and Giorgio Parisi, were awarded the prize in Physics on Tuesday for contributing to our "understanding of complex systems".
German chemist Benjamin List and UK-born David MacMillan were awarded the prize in chemistry on Wednesday for the discovery of asymmetric organocatalysis which helped make "chemistry greener."
The Nobel Prize in Literature was awarded on Thursday to novelist Abdulrazak Gurnah “for his uncompromising and compassionate penetration of the effects of colonialism and the fate of the refugee in the gulf between cultures and continents.”