Startup founder, small business owner, retired hotelier, and project manager with 9+ years of customer facing experience. Also: geek, alpine race coach, lover of great beer, and hooked on digital marketing.
Smith Travel Research (STR.com) has an array of reports and resources that provide insight into hotel industry metrics. There are roughly 7 type of market segments, defining what segment you want to look at will inform what type of metrics you need to look at.
Matt Knight was right on with recommending that you use RevPAR, ADR, and Occupancy history + projections; they are the industry's leading indicators for overall health of property.
I was a hotelier for 9 years and worked with an array of companies at properties across the United States at a 3, 4, and 5 star level. If you have any questions I'd be happy to help.
Chris