Short answers, pulled from the story.
The Australian federal budget established an income threshold of A$70,000 for the Medicare Levy Surcharge in 2008. This surcharge applies to individuals with high annual incomes who do not purchase specified levels of private hospital coverage.
President Obama signed the Affordable Care Act into law in 2010 which included an individual mandate effective in 2014. Final regulations for the mandate appeared in the Federal Register on the 30th of August 2013.
Supporters of the individual mandate as a free-market approach included Charles Grassley, Mitt Romney, and John Chafee. The Heritage Foundation proposed an individual mandate to purchase healthcare in 1989 as an alternative to single-payer systems.
Chief Justice John Roberts delivered the majority opinion in National Federation of Independent Business v. Sebelius on the 28th of June 2012. The U.S. Supreme Court upheld the provision as constitutional by a 5, 4 vote.
More than 97 percent of Massachusetts residents became insured following implementation of the 2005 Massachusetts health care reform law signed by Governor Mitt Romney. This made it the state with the lowest percentage of people without health insurance.