One of the most popular Kendrick Lamar shows of 2018 was Friday May 25th at Cellairis Amphitheatre at Lakewood. Interest for that show was at its highest when ticket sales began. The interest resulted in high ticket prices that dropped as the show neared.
Across all Kendrick Lamar shows in 2018, interest was strongest right when the shows were announced and tickets went on sale. Meanwhile, ticket prices typically increased about 15 - 20% from the date a show was announced until the days leading up to the show.