I would say that it would be a good idea to track the effect that the downturn in the economy has had on the hotel industry. When individuals are worried about job security or have lost their job, the idea of taking a vacation or planning a vacation go to the bottom of the priority list.
Sadly, when ordinary can't make vacation plans, and don't book hotel rooms, jobs in the hotel industry are lost. You can also include the business traveler, who uses hotels in order to do business in other states, cities and countries. When business is slow, travel slows down, so business to business travel as well as personal travel have a direct impact on the hotel industry.
There are many different types of customers for the hotel industry, including everything from holding weddings, parties to holding business seminars.
It is an interesting topic to research, it would also be interesting to look into how the hotel industry copes with economic downturns that result in less travel.