10 Countries with the Largest Population Decline in the Last Decade

The World Bank notes that the global population reached 7.8 billion in 2021. This represents an increase of 832 million (11%) compared to 2011, when it stood at 7.0 billion.

However, several countries experienced population decline due to prolonged conflicts and wars resulting in killings, migration, and falling birth rates.

Syria experienced the largest population decrease in the last decade (2011-2021), losing 2.81 million people (13.31%), resulting in a population of only 18.28 million. Prolonged conflict and war, causing numerous casualties, led to this population reduction.

The next largest population decline was in Japan, with a decrease of 2.15 million (1.68%), resulting in a population of 125.68 million in 2021. This was followed by Ukraine, which lost 1.89 million people (4.14%), leaving a population of 43.81 million, and Romania, which saw a decrease of 1.03 million (5.12%), resulting in a population of 19.12 million.

Greece also experienced a population decrease of 440,000 (3.97%) over the decade, reaching 10.66 million in 2021. Puerto Rico's population shrank by 415,150 (11.29%) to 3.26 million, and Bosnia and Herzegovina saw a decrease of 397,710 (10.86%), also resulting in a population of 3.26 million.

Serbia's population decreased by 390,000 (5.39%) over the 10-year period, reaching 6.84 million, while Croatia's population fell by 381,620 (8.92%), leaving a population of 3.9 million.