China's economic expansion slowed to 7.8 percent year on year in 2012 amid external jitters and domestic woes, data from the National Bureau of Statistics showed Friday.

The growth rate, the weakest expansion in a decade, was down from 9.3 percent in 2011 and 10.4 percent in 2010.

The economy's fourth-quarter growth quickened to 7.9 percent on government pro-growth measures. The rate ended a seven-straight-quarter slowdown.

In 2012, the gross domestic product reached 51.93 trillion yuan (8.28 trillion U.S. dollars).

The government pared the full-year growth target for 2012 to 7.5 percent from 8 percent in early 2012.