A woman has her blood pressure taken at the Care Harbor four-day free clinic, which offers free medical, dental, and vision care to around 4,000 uninsured people in Los Angeles.

According to the Commonwealth Fund, which regularly ranks the health systems of a handful of developed countries, the best countries for health care are the United Kingdom, the Netherlands, and Australia.

The lowest performer? The United States, even though it spends the most. “And this is consistent across 20 years,” said the Commonwealth Fund’s president, David Blumenthal, on Friday at the Spotlight Health Festival, which is co-hosted by the Aspen Institute and The Atlantic.

Blumenthal laid out three reasons why the United States lags behind its peers so consistently. It all comes down to:

A lack of insurance coverage. A common talking point on the right is that health care and health insurance are not equivalent—that getting more people insured will not necessarily improve health outcomes. But according to Blumenthal: “The literature on insurance demonstrates that having insurance lowers mortality. It is equivalent to a public-health intervention.” More than 27 million people in the United States were uninsured in 2016—nearly a tenth of the population—often because they can’t afford coverage, live in a state that didn’t expand Medicaid, or are undocumented. Those aren’t problems that people in places like the United Kingdom have to worry about. Administrative inefficiency. “We waste a lot of money on administration,” Blumenthal said. According to the Commonwealth Fund’s most recent report, in the United States, “doctors and patients [report] wasting time on billing and insurance claims. Other countries that rely on private health insurers, like the Netherlands, minimize some of these problems by standardizing basic benefit packages, which can both reduce administrative burden for providers and ensure that patients face predictable copayments.” In other words, while insurance coverage in general is great, it’s not ideal that different insurance plans cover different treatments and procedures, forcing doctors to spend precious hours coordinating with insurance companies to provide care. Underperforming primary care. “We have a very disorganized, fragmented, inefficient and under-resourced primary care system,” Blumenthal added. As I wrote at the time, in 2014 the Commonwealth Fund found that “many primary-care physicians struggle to receive relevant clinical information from specialists and hospitals, complicating efforts to provide seamless, coordinated care.” On top of a lack of investment in primary care, “we don’t invest in social services, which are important determinants of health” Blumenthal said. Things like home visiting, better housing, and subsidized healthy food could extend the work of doctors and do a lot to improve chronic disease outcomes.

Together, these reasons help explain why U.S. life expectancy has, for the first time since the 1960s, recently gone down for two years in a row.