No big surprises again from China’s economic data for 2015--but also not much brightness either. The government’s statistics bureau on Tuesday released the economic growth rate for the fourth quarter and all of last year, plus a slew of other numbers gauging the performance of the world’s second largest economy.

The picture that emerges is of an economy wrestling with a deepening slowdown, one that’s projected to persist. Growth fell to 6.9% in 2015--the weakest pace in a quarter century--and hit 6.8% in the fourth quarter,...