Billboard has revealed their year-end list of top country radio singles, and no solo female artists are included in the Top 10 songs. No male-female vocal groups make the cut, either: With only one exception, every song in the Top 10 year end list is by a solo male artist.

Brantley Gilbert's duet with Lindsay Ell, "What Happens in a Small Town," does make the list, coming in at No. 3. Aside from Ell, though, no women appear in the Top 10, even as featured artists. Morgan Wallen tops the chart with "Whiskey Glasses," followed by Luke Combs (twice!), Justin Moore, Luke Bryan, Cole Swindell, Jason Aldean, Scotty McCreery and Lee Brice.

In fact, only one solo female artist enters the year-end Top 20. Kelsea Ballerini clocks in at No. 12 with "Miss Me More." Maren Morris' "Girl" follows, at No. 26, and Carrie Underwood's "Southbound" appears at No. 36. "Buy My Own Drinks" by Runaway June and "Love Wins"  by Underwood also come in under the Top 50.

It's no secret that country radio disproportionately favors male artists. In December of 2018, the Billboard Country Airplay chart contained no female artists in its Top 20 for the first time since the chart's inception in January 1990. At the time, data showed that female artists have seen a steady decline in representation at radio every year since 2015, with an overall downward trend since 2000.

In late 2019, another study revealed that gender bias at country radio crowds female artists out of airplay, no matter what time of day it is.

These Are Country Radio's Top 10 Songs of 2019:

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