According to the U.S. Bureau of Labor Statistics, prices for car and truck rental were 20.36% higher in 2018 versus 1997.
Between 1997 and 2018: Car and truck rental experienced an average inflation rate of 0.89% per year. In other words, car and truck rental costing $20 in the year 1997 would cost $24.07 in 2018 for an equivalent purchase. Compared to the overall inflation rate of 2.11% during this same period, inflation for car and truck rental was lower.
Raw Consumer Price Index data from U.S. Bureau of Labor Statistics for Car and truck rental: