Bangkok is the world's top destination city by international overnight visitor arrivals, according to an annual ranking released Thursday.

The Thai capital is projected to receive 21.47 million international overnight visitors in 2016, the Mastercard Global Destinations Cities Index showed, ahead of London, which will receive 19.88 million, and Paris, which will welcome 18.03 million.

The index projects visitor volume and spend estimates for the 2016 calendar year.

Istanbul, which was ranked fifth in the 2015 list, was placed eighth this year amid a slowing growth in arrivals. While the annual average visitor growth rate for 20 cities of the list was 5.6 percent in 2016, Istanbul's visitors only increased by 0.3 percent in 2016, only behind Hong Kong with 0.2 percent.

Dubai, which is expected to receive 15.27 million visitors in 2016, tops projected international visitor spending at 31.3 billion dollars, far ahead of London, where visitors are expected to spend 19.8 billion dollars. Among the top ten cities of the list, which all are projected to receive over 10 million visitors, Istanbul's visitor spending expectation remained the lowest at $7.5 billion.

The index estimated that 90.8 percent of Istanbul's visitors choose the city for leisure and other purposes, while business visits remained at the lowest with 9.2 percent. On the contrary, 54.6 percent of Shanghai's visitors are expected to arrive in the city for business purposes.

When the expenditure of visitors were concerned, the average accommodation expenditure rate in total visitor spending was the lowest in Istanbul with 20.4 percent. This rate was the highest in Paris, where visitors spend an average 44.8 percent of their travel budget.

Travelers allocated most of their budget to shopping in East Asian cities of Seoul, Osaka, Tokyo, Taipei, Hong Kong, Kuala Lumpur and Shanghai with respective rates for shopping as 58.7, 43.4, 43.1, 33.9, 30.9, 30.7 and 28.6 percent. London was the only European and North American exception with an average of 46.7 percent travelling budget spared for shopping.

Tourism arrivals in Bangkok have remained strong despite a rash of negative headlines, and the number of visitors are expected to increase by 9.6 percent compared to last year. Last month, a series of coordinated bomb attacks, some of them in popular tourism destinations, left four people dead and dozens injured. Police said the attacks were not "terrorism related" but rather the work of southern Muslim separatists.

A year earlier, in August 2015, a shrine bombing in central Bangkok killed 20 people, mostly foreigners, while injuring more than 100. The country has been under military rule since a coup in May 2014.

Whereas in Istanbul, a string of terrorist attacks and suicide bombings by PKK and Daesh terrorist groups, in addition to a failed coup by the Gülenist Terror Group (FETÖ) on July 15, has hampered the city's tourism boom. Istanbul's visitor growth rate projection was the highest among top 20 cities in 2015's index with 11.4 percent, whereas this year, it barely stood on the positive side with 0.3 percent.