In which quarter, on an average there is maximum negative deviation of the output from the average value of trend of that quarter?

Quarters with negative deviation from its trend

Average deviation for any quarter  = Sum of all deviations from the quarter / Number of years

By observation, Quarter 1 will be rejected as all its deviations are positive.

Average deviation for quarter 2  =  ((63-64.5) + (59-61.12) + (55-55.25))/3 = (-1.5-2.12-0.25)/3 = -3.87/3

Average deviation for quarter 3  =  ((56-60.38) + (63-65.5) + (56-58))/3 = (-4.38-2.5-2)/3 = -8.88/3

Average deviation for quarter 4 =   ((61-61.38) + (67-65.25) + ( 52-56.25 ))/3 = (-0.38+1.75-4.25)/3 = -2.88/3

Quarter 3 has maximum average negative deviation.