An online product or service listing arrangement logs searches performed and uses the logged information to calculate a scarcity index that measures the scarcity of products and services. Scarcity may indicate the number of searches that consumers have conducted compared to available listings. Empirical techniques are used to take into account certain types of searches that may not accurately reflect actual consumer demand. Reports may compare item scarcity within different geographical or other markets to determine relative scarcity. Particularly advantageous but non-limiting applications include new and used motor vehicles, employment opportunities, and real estate.