Sony shipped 14.8 million PS4s during its fiscal year 2014 (ended March 31, 2015), after shipping 7.5 million systems for fiscal 2013 (ended March 31, 2014).
PS4 sales were not tallied for fiscal 2012, since that period ended March 31, 2013--eight months before the console went on sale in November 2013.
Overall, Sony's Game & Network Services division--which houses PlayStation--posted year-over-year gains for revenue and operating profit. This growth was led in part by an increase in PS4 hardware unit sales and a "significant" jump in network services revenue (i.e. PlayStation Network), but partially offset by falling PlayStation 3 hardware and software sales.
The PS4 still has a lot of work to do to catch its predecessor, as the PS3 has sold more than 80 million units worldwide as of November 2013. But the PS4 is showing positive signs of being able to do that someday, as the console is outselling the PS3 at the same period in their respective lifecycles.