This was done based on 2019 prices...
Disneyland admission cost $2.50 in 1955 compared to a $129 “regular” park ticket today, an increase of 5,060%, according to the study. Disneyland admission today costs more than 50 times as much as it did on opening day, the study found. Adjusted for inflation that ticket would be $23.89 in 2019.
The 1955 Disneyland admission price was based on an adult “Deluxe 15” ticket book that included admission to the park and 15 attractions.
Scary how much we are willing to pop at these days.