The medical expenses of Formula 1 legend Michael Schumacher have now exceeded $15 million, according to reports. The record seven-time world champion was in a coma for six months after a skiing accident in the French resort of Meribel in December 2013 left him fighting for his life.

After coming out of the induced coma at a hospital in Grenoble, the retired German racer was transferred to a facility in Lausanne before last September returning to his family home on the shore of Lake Geneva. There have been reports that a medical facility was installed in the Swiss mansion, with a 15-strong team of medical expert assigned to the 46-year-old.

And British newspaper the Daily Mirror has now claimed that the medical costs have averaged $154,000 a week since suffering his severe head injury, and now total in excess of $15 million. According to a report from global wealth intelligence firm Wealth-X earlier this year, Schumacher is the richest Formula 1 driver of all time, amassing a fortune of $780 million. Schumacher raced in F1 from 1991 to 2006, amassing a record haul of championships, race wins and pole positions. He returned to the sport in 2010 and drove with Mercedes for three years.

Since his accident Schumacher’s family is thought to have sold a holiday home in Norway as well as a private jet.

Schumacher’s wife Corinna has worked hard to preserve their privacy, revealing few details about his condition. The guarding of the family’s privacy has been enforced by Schumacher’s long-time manager Sabine Kehm.

“Michael always had strict rules that we worked out together,” she told German newspaper Der Spiegel in June. He kept his job strictly separately from the private side, and he never deviated from that. There was never a 'home story', and no journalist ever had his phone number.

The previous week, Kehm provided what is still the most recent official update on Schumacher’s condition, when saying that he was “making progress,” but stressed that people “must always keep the seriousness of his injuries in mind.”

Still, there have been various unconfirmed reports on Schumacher’s condition. In January this year Italian publication Corriere della Serra reported that he cried when hearing his wife and two children.

“Sometimes a tear rolls down Michael's face,” the story said, via The Telegraph. “He cries when he hears the voice of his children or his wife. Michael has his eyes open but he is often looking into a void. In recent times he has been able to recognize the familiar faces of his family but he cannot communicate with them. He does not speak and he is not able to perform movements independently. He reacts to external stimuli but for now can only answer a familiar voice by opening his eyes.”