Avik Roy, who serves as GOP presidential candidate Marco Rubio’s health care advisor, suspects United may just be the first domino to fall. Other commercial insurers, such as Aetna, Anthem, and Cigna, have raised premiums by double digits and still say they can’t make the numbers work in their favor. Hence, they have withdrawn from counties where their losses were particularly acute.

UnitedHealth Group’s shock $425 million downgrade to its earnings forecast for 2015 was almost entirely driven by losses on the ObamaCare exchanges. UnitedHealth is the largest U.S. insurer by enrollment, and the company is warning it may withdraw from ObamaCare in 2017. The insurer has already suspended advertising for its ObamaCare coverage and stopped paying commissions to insurance brokers for signing people up.

James Capretta & Joseph Antos argue that one of the most consequential provisions of the Affordable Care Act is also one of its most obscure. The “productivity adjustment factor,” inserted by the ACA into the Medicare program, is a massive spending cut included to make room in the federal budget for the ACA’s expensive new health insurance subsidies. If Congress follows past practice, the ACA’s higher spending will be with us long after savings from the productivity adjustment factor have been reduced or eliminated altogether.

The Centers for Medicare & Medicaid Services has proposed mandating minimum network standards for health plans sold on the federal marketplace in 2017 as part of an effort to handle the broad shift toward narrow provider networks. The Affordable Care Act requires that all medical policies on the exchanges have enough in-network hospitals and doctors for members so that “all services will be accessible without unreasonable delay.” However, the 381-page proposed rule (PDF) released Friday goes a step further, asking states to establish a quantitative measure to ensure ACA policyholders have sufficient access to healthcare providers.

The annual rate of healthcare inflation is at a 6 decade low. At the end of the day, reasonable people will disagree about the exact proportion of credit ObamaCare deserves and neither side has (or will have) conclusive empirical evidence to prove their view beyond a shadow of a doubt. In reality, parsing out credit for the slowdown in health inflation is less relevant than the far more important question to average Americans (and policymakers): will this slowdown continue?

This week, newspapers donned headlines about the sharp rise in premiums for health insurance plans available this open enrollment season on the ObamaCare exchanges. Increased premiums paired with sky-high deductibles have consumers paying for catastrophic health insurance at comprehensive-plan prices. Ed Morrissey argues that consumers have become “victims of a bait-and-switch scheme that the government would vigorously prosecute – if it wasn’t masterminding the scheme itself.”

UnitedHealth Group just announced they expect to lose $700 million in the Obamacare exchanges and are seriously considering withdrawing from the program in the coming year. Why is this happening? Because nowhere near enough healthy people are signing up to pay for the sick. The Robert Wood Johnson Foundation and the Urban Institute have come to largely the same conclusion—enrolling a total of 10 million in the exchanges, based on historic trends, would mean only about 9 million of them would be subsidy eligible. That would amount to only 38% of the 24 million people eligible for a subsidy.

The Urban Institute’s Robert D. Reischauer and Brookings Senior Fellow Alice M. Rivlin highlight three main health care issues the candidates should focus on that are likely to dominate the election debate. Republicans must form consensus around a replacement plan for the Affordable Care Act and Democrats must develop ways to improve the law. Both must focus on how to control rising health spending and how to preserve Medicare for the growing elderly population.

One of the untold elements of the rapid decay underway in the ObamaCare exchanges is the massive shift toward the Medicaid managed care companies, and away from the traditional commercial insurers like UnitedHealth Group and Aetna. In short order, ObamaCare is evolving into a Medicaid marketplace. Not only in terms of the design and quality of the narrow-network plans that are being offered, but in the actual carriers that sell those policies.

The new individual marketplace created under ObamaCare was intended to rival that of the employer sponsored insurance marketplace in stability and predictability, while premiums were to rise at rates much lower than the historical average. This study from the American Action Forum evaluates the degree to which these promises have been fulfilled. AAF found that the cost of both the benchmark Silver plan and the lowest cost Bronze plan will increase by 10% in 2016.