nag_tsa_diff (g13aac) Example Program Results Non-seasonal differencing of order 2 and seasonal differencing of order 1 with seasonality 4 are applied The output array holds 20 values, of which the first 14 are differenced values -11.0 -10.0 -8.0 4.0 12.0 -2.0 18.0 9.0 -4.0 -6.0 -5.0 -2.0 -12.0 5.0 2.0 -10.0 -13.0 17.0 6.0 105.0