We also perform analyses of four sub-categories separately, including agricultural goods (SITC 0, 1, 2 and 4 excluding 27 and 28, i.e. primary products minus fuels and mining products), manufactured goods (SITC 5 to 8 excluding 667 and 68) and two sub-categories of manufactured goods: chemical products (SITC 5) and machinery and transport equipment (SITC 7).