There's really no surprise that revenues are down at Burbank's Bob Hope Airport. I am an infrequent flier, and have utilized the Burbank airport for nearly 45 years.
I recall the days when you could fly to most every major city out of Burbank Airport, non-stop. Now you must pay the same short-term parking rate as at Los Angeles International Airport, $31 per day. No wonder parking revenues are down. And you can no longer fly to many U.S. cities non-stop from Burbank. In fact, there are very few places you can get to non-stop. It takes practically a full day to get anywhere. Also, some airlines have discontinued many of their flights, and one airline has pulled out completely.
Also, ticket prices out of Burbank have gone up to the stratosphere. Years ago I would fly mostly out of Burbank and seldom out of Los Angeles. Now it's just the opposite. I rarely go out of Bob Hope Airport, although that is my preferred airport.