Teen driving deaths increased sharply in the first six months of 2012, according to a new report from the Governors Highway Safety Association.

The report shows that 16- and 17-year-old drivers died in traffic accidents at a rate of more than 19 percent than the same time period the previous year.

The increase reverses a decade-long decline in highway deaths.

There is no reported cause for the increase, but new distractions like smart phones are thought to be one of the causes.

Federal data on traffic deaths for 2012 will be available later this year. An increase in traffic deaths overall is expected.