I am not sure about the worth of comparing this January's figures with last years figures, as that time last year the route was to LCY and not STN.
From the other posts it is clear that STN has been less popular than LCY, however the difference in passenger numbers between the two routes seems to have lessened.
...month of September...23% down on same month last year
down 19% on last Jan
As has been said before STN is cheaper to operate to than LCY, and there is a PSO in place. This will help the bottom line of the airline, but then again, who knows if these figures are good or not?