Hot country stations may also include non-country pop songs in their rotation. A late-2010s format known as "The Wow Factor" attempted to cross the adult country format with classic hits. Its juxtaposition of country and pop bore similarity to the adult hits format. By 2020, The Wow Factor had largely cut its country titles. Americana: A more recent and emerging format which plays more Modern "Authentic Country music" that often plays music from the modern country subgenres of Americana and Alt-Country, along with roots music. Classic Country is also common on these stations and are often from the Honky Tonk, Hillbilly, Bluegrass, Western Swing, Bakersfield sound, and Outlaw Country subgenres. The station musical libraries usually varies from station to station as some stations might add in a few rock and mainstream country artists that have a more traditional country influence. This type of station format is the biggest in Texas with Texas Country/Red Dirt music radio (with examples being KFWR and KHYI), this format is also popular online and for shows on public radio and college radio stations. Dividing line With a few exceptions, the classic country genre has struggled as a radio format (unlike mainstream country stations). While it has a fiercely loyal audience, classic country stations often struggle to find advertisers. While advertisers are primarily interested in the 18 to 49-year-old demographic age group, classic country usually attracts an older audience. For perhaps that reason, country music fans are often (stereotypically) divided into two camps: The younger country music fan (with the exception of the Americana roots music fans), especially if he or she is younger than 30 years old, who is largely unfamiliar with the older country music sounds, especially from the 1980s and earlier, and will find earlier pre-1960s "hillbilly" music (such as that by Hank Williams and Kitty Wells) and its unpolished, Appalachian influences over-the-top and unlistenable. The classic country fan, frequently over the age of 50, who—with a few exceptions—often dislikes country music produced after 1990, when the genre began incorporating more rock influence. Such fans often bemoan the electrification of popular country music with the addition of heavier guitars, Hard Rock influenced voices and harder percussion (for example, the music of Brantley Gilbert and some of Jason Aldean's discography), and in more recent years even hip hop influences. Other complaints from this era include the increased cliché-driven songwriting ("Achy Breaky Heart" by Billy