Currently, an estimated 60.7 million call the country home, but the statisticians expect that number to drop to 58.6 million over the next 30 years, and to 53.7 million by 2065. The number-crunchers published their predictions on Wednesday, in a report titled 'The demographic future of the country'.
Of course, a lot could happen over the coming decades to affect the country's birth and death rates as well as immigration figures, but Istat predicts there is only a seven percent chance that the national population will increase by 2065. The agency's estimates range from a minimum of 46.1 million to a maximum of 61.5.
The most likely scenario, Istat believes, is that the southern and island regions will see a steady decrease in population over the next 50 years.
Meanwhile, the population of the more prosperous centre-north is only expected to decrease from 2045 onwards. By 2065, there's a 31 percent chance that the central-northern population will have increased from today's number, while in the south, that probability is close to zero.
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The centre-north is already more populated than the south, and this trend is projected to become even more marked.
Currently, 66 percent of people live in the centre-north and 34 percent in the southern and island regions. By 2065, that ratio is likely to shift to 71:29.
But what are the factors behind these expected changes?
For starters, life expectancy will increase.
Today, a baby born in Italy has an average life expectancy of 80.1 years if male and 84.6 years if female. But those babies' grandchildren, if born in 2065, will likely be expected to live to 86.1 or 90.2 years, depending again on their gender.
Italy's slow birth rate - which hit a record low this year - is also predicted to see an increase, but this won't be enough to balance out annual deaths - leading to the projected population decline.
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Another factor which will have an important impact on demographic changes, but which is particularly hard to predict, is international migration.
Istat's experts predict that net migration will remain positive, meaning higher numbers of people will come to Italy than leave the country.
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