then withdraw money tax free to pay for qualified expenditures. To qualify for an HSA, the purchaser must also have a qualifying high-deductible health insurance plan. Over time, participants are allowed to contribute more (cumulatively) to the savings account than would be required to fulfill their annual deductible for a given year (although annual limits on pre-tax contributions [other than a 1-time IRA rollover option] are well below the annual deductible), and any unused portions of the account accrue without tax penalty so long as the funds are used only for qualified medical expenses. Further enhancements to HSAs went into effect in 2007. The combination of tax breaks for premiums and the health savings account as well as a tax subsidy to pay for the catastrophic insurance premium of lower income individuals has boosted the popularity of these plans. By April 2007, some 4.5 million Americans were enrolled in HSAs; more than a fourth of those were previously uninsured. Only people enrolled in high-deducible health plans are eligible for HSAs. Another type of account in the consumer driven healthcare model is Health Reimbursement Arrangements (HRAs), which are employer-funded, and in which employers receive the tax benefits. These accounts are available to people that do not qualify for HSAs. Other countries with experience in this type of health insurance include China, Taiwan, Singapore and South Africa. Popularity By 2007, an estimated 3.8 million U.S. workers, about 5% of the covered workforce, were enrolled in consumer-driven plans. About 10% of firms offered such plans to their workers, according to a study by the Kaiser Family Foundation. In 2010, 13% of consumers in employee-sponsored health insurance programs had consumer-driven health plans. In 2016, 29% of employee were covered by a CDHP. According to economist John C. Goodman, "In the consumer-driven model, consumers occupy the primary decision-making role regarding the healthcare they receive." Goodman points to a McKinsey study which found that CDHC patients were twice as likely as patients in traditional plans to ask about cost and three times as likely to choose a less expensive treatment option, and chronic patients were 20% more likely to follow treatment regimes carefully. In 2014, when major portions of the Patient Protection and Affordable Care Act are implemented in the United States, high deductible plans and the concept of consumer-driven healthcare may become more popular. Although new federal tax subsidies will help reduce health insurance rates