;(5);(9);(6);(10);(7);(11)
OLS;GAMMs;OLS;GAMMs;OLS;GAMMs
constant;–0.674***;0.040***;–0.413***;0.040***;–0.076***;0.040***
GDP;–0.060***;"3.059 (7.69)**";–0.060***;"3.939 (1.18)***";–0.060***;"3.741 (4.85)***"
POP;0.050***;"2.294 (9.83)***";0.030***;"3.732 (8.35)***";0.057***;"2.734 (2.65)***"
OIL;–0.020*;"2.737 (1.09)";0.078;"3.703 (3.69)*";–0.023;"2.099 (1.98)**"
LIBDEM;–0.152***;"3.569 (5.84)***";–0.111***;"2.123 (5.979)***";–0.168***;"1.981 (12.11)***"
USA;0.364***;"3.699 (5.766)***";–;–;0.487***;"3.990 (8.64)***"
CHINA;–;–;–0.172;"2.379 (2.939)**";–0.528**;"3.393 (5.29)***"
"R
              2";0.724;0.935;0.693;0.822;0.742;0.894