He's had an injury hit season. Welbeck has played consecutively for months as the sole striker. Falcao's had almost half the playing time, in his first season in the PL.
in the PL: Falcao 864 mins, 4 goals
Welbeck 1432 mins, 4 goals.
Falcao is on the wane, nowhere near his AM performances, but he's still a good striker.