BPS head Suhariyanto said the Mount Agung eruption, which happened in Indonesia’s most popular tourist destination Bali in November, was most responsible for Indonesia not meeting the target.

“The eruption played a big part, since tourist arrivals usually spike in November and December,” Suhariyanto said in a press conference.

The two months are typically the peak tourist seasons of the year.

Indonesia first raised its warning level for Mount Agung in September before the volcano finally erupted in November.

Around one million overseas visitors canceled their trips to Bali because of the eruption, Tourism Ministry data showed.

That was why in November Indonesia suffered its first setback in foreign tourist arrivals since December 2015, down 0.81 percent to 848,641.

In December, the fall in the number of foreign tourists was even bigger: 5.77 percent from the same period in 2016, with a total of 902,602 foreign tourists.

From January to September, Bali welcomed 4.5 million foreign tourists, nearly half of the 10.5 million visiting Indonesia in that period.

The Natural Disaster Mitigation Agency, or BNPB, reported that Mount Agung’s eruption caused approximately Rp 9 trillion ($490 million) in losses to the local tourism industry.

Last year, tourism was the second largest contributor to Indonesia’s foreign exchange revenue after crude palm oil exports with $16.8 billion.

It is expected to generate $20.4 billion this year, assuming tourists spend $1,200 on average while on holiday in the country, ministry data showed.

The ministry has set a target of 17 million foreign tourist arrivals this year.