On April 7, Seoul Metro released an analysis of their Seoul subway advertisements throughout 2019!

Subway advertisements are frequently used to show support and congratulate celebrities for their birthdays, anniversaries, accomplishments, and more. The total number of Seoul subway advertisements last year was 10,468, with 21 percent being taken up by idol advertisements at 2,166. In 2014, this total was 76, with the number growing exponentially each year, finally reaching over 2,000 in 2018.

With the establishment of the “Produce 101” series in 2016, subway advertisements saw a massive increase, as fans began to promote their favorite trainees, encouraging civilians to participate in voting. This has expanded the spectrum of subway advertisements, moving from singers and actors to include trainees, professional gamers, musical theatre actors, and many more. They are also occasionally used by regular civilians to congratulate family and friends on birthdays, graduations, and more.

In 2019, BTS recorded the top number of ads, with a total of 227, accounting for 10.5 percent of all idol advertisements. They were followed by EXO with 165, Wanna One with 159, NCT with 127, NU’EST with 44, and SEVENTEEN with 41.

The top girl group was IZ*ONE with 40, followed by TWICE and BLACKPINK with 22 each.

For individual advertisement rankings, BTS’s Jungkook had 46, followed by EXO’s Baekhyun and BTS’s V with 35 and 31, respectively.

Many veteran groups were also featured, such as Super Junior (40), H.O.T (22), Shinhwa (7), T-ara (6), SECHSKIES (4), and Baby V.O.X (1).

Idol subway advertisements are commonly placed at popular stations along line two, including Gangnam, Samsung, Hongdae, and Hapjeong station. Apgujeong station along line three and Myeongdong station along line four are other popular locations.

The cost of these advertisements depends on its location, size, type, and more. On average, a large, bright advertisement at a popular station costs around 4.5 million won (approximately $3,700) a month.

Source (1) (2)