Tourism is measured using a combination of quantitative and qualitative metrics that track the flow of people and money. The most traditional indicator is Visitor Arrivals, which counts the number of overnight tourists entering a destination. This is complemented by Average Length of Stay and Hotel Occupancy Rates, which provide insight into how long travelers are staying and how well local infrastructure is utilized. From an economic perspective, Tourism Expenditure tracks the total amount of money spent on lodging, food, and activities, while Tourism's Contribution to GDP measures the sector's overall impact on the national economy. In 2026, the industry has shifted toward measuring Sustainable Tourism Indicators, such as "economic leakage" (how much profit stays local), resource consumption per visitor (water and energy), and "Social Carrying Capacity," which gauges local resident sentiment toward tourism levels. Advanced data analytics now also utilize mobile roaming data and credit card transactions to map visitor dispersion, helping destinations move beyond simple headcount to understand the true "quality" and impact of their tourism industry.