The end of the year is rapidly approaching, and seasonal variations in how Americans listen to the radio are influencing stations everywhere as December marches on. For some, this time of year is all about holiday music and its far-reaching effects across the radio dial. Over the next few weeks, the full impact of stations that flipped to an all-Christmas format will become apparent in Nielsen’s portable people meter (PPM) markets. For others, the end of the year marks both the chance to take stock of larger macro trends that can reveal shifting consumer taste and take advantage of the most important stretch of the calendar for sports listening.

With the release of the November audience trends, Sports radio stations are seeing the annual upswing that happens each year when football moves back to the top of the fandom food chain and the major league baseball season concludes with a thrilling month of playoffs. Since June, the audience shares for sports-formatted stations have risen more than 30%.

Both the National and American League Championship baseball series took place during the November survey (which ran from Oct. 12 to Nov. 8), as did the World Series, which went to a deciding game seven for the second year in a row. These contests had a notable impact on sports radio listening, especially since the teams hailed from major markets. In each of the past two years, major market teams have played in the World Series, and fan attention has been enormous.

The following chart details the average in-game audience share for the local-market flagship broadcast stations, including both the English and Spanish-language affiliates.

But radio listening didn’t just spike in markets where there was local interest. Sports radio across the U.S. saw upticks this month, and the World Series was clearly a factor. However, the size of the audience share for the specific flagship stations in the local market varies year-to-year due to many factors, including the size of that market’s total radio-listening pie, start times of the games due to time zone differences, TV viewership and fan passion.

On the music radio front–and particularly among formats that favor both popular and urban music–November offers an opportunity to take stock of how preferences have changed in the past five years. When assessing the audience share among Millennials (those aged 18-to-34) there are three formats which share a significant amount of audience, depending on the music cycle: Pop Contemporary Hit Radio (CHR), which is the top-ranked format for Millennials, it’s rhythmic-leaning cousin Rhythmic CHR, and of course Urban Contemporary which often identifies as hip-hop.

Since 2012, Urban Contemporary has moved from being the seventh-most popular format among Millennials to the fifth-most popular today (rising from a 5.0% share to a 6.5% share). At the same time, Rhythmic CHR has declined from the third-ranked format to the sixth-ranked format now (falling from a 7.2% share to a 4.9% share). Pop CHR has maintained the top spot and is one of the largest radio formats overall, but over the past 18 months the format has trended flat to slightly down. This final chart tracks the 18-34 shares for each format since the start of 2012.

Over the next few weeks we will dive deeper into the trends for the major radio formats during the calendar year, and parse out the specifics of the holiday music lift coming to all-Christmas stations this month.

Data used in this article is inclusive of multicultural audiences. Hispanic consumer audiences are composed of both English and Spanish-speaking representative populations.