Traditional Medicare / Title XVIII reported inpatient days declined by 53.4% over the period, while Medicare Advantage / HMO inpatient days increased by 237.1%. When both categories are combined, total Medicare-related inpatient days increased by 69.4%.  In the most recent year, Puerto Rico hospitals reported approximately 120,866 traditional Medicare inpatient days and approximately 640,167 Medicare Advantage / HMO inpatient days, for a combined total of approximately 761,033 Medicare-related inpatient days. This view separates traditional Medicare from Medicare Advantage / HMO volume and avoids treating Title XVIII reported days as the full Medicare-related inpatient total.

The growth in Medicare-related hospital activity did not occur through traditional Medicare. It occurred primarily through Medicare Advantage. This distinction is strategically important for hospitals because payer contracting, utilization management, authorization practices, reimbursement terms, and market concentration increasingly shape Medicare-related inpatient economics.