Once September rolls around in Japan, Halloween is absolutely inescapable—all the cute pumpkin decorations and orange-dyed foods put America’s pumpkin-spice craze to shame. The weekslong build-up culminates in huge costume parties in the streets of Tokyo and other cities.

According to the Japan Anniversary Association, which registers and tracks commemoration days, the 2016 market (link in Japanese) for everything from shopping to Halloween-themed dining reached ¥135 billion ($1.2 billion), surpassing Valentine’s Day (¥134 billion) spending. That makes it the second-biggest event in Japan after Christmas. (The association says that because of poor weather in the winter of 2014 that led to logistical difficulties, its estimate of ¥108 billion yen for the market size for Valentine’s Day that year should be discounted.)

The association, whose latest inventions (link in Japanese) include “lactobacillus day,” which falls on the 23rd of each month, and “sesame day” on Nov. 5, suggests a few reasons for Halloween’s rise in Japan. The notion that “Halloween means dressing up” has become normal, and costumes are widely available—the association says Amazon had some 180,000 items for dressing up for sale last year—and people feel less worried that they might be the only person in costume.

Last year was also a particularly big year (link in Japanese) for Halloween, said the Japan Anniversary Association, because the popularity of group-friendly games like Pokémon Go helped bring people out to the streets, while the success of movies like the new Godzilla and anime hit Your Name encouraged people to dress up as characters from those films. Prime minister Shinzo Abe’s appearance as Super Mario—already a mainstay of Japanese cosplay—at the closing ceremony of the Rio Olympics last year also gave Italian plumbers another boost at Halloween.

However, the market size for Halloween in 2017 is expected to be about 3% less than last year, said the group, blaming the drop (link in Japanese) in part on the October general election that may have taken media attention away from Halloween. One idea it has for making Halloween even bigger is to incorporate more seasonal elements in it, turning it into an “Autumn Jumbo Halloween.”