FTA_2ijt takes a value of one if exporter i belongs to the ACFTA in year t and destination country j does not and zero otherwise.
A positive and statistically significant coefficient of FTA_2ijt is defined as a trade creation effect in term of exports and indicates
that regional integration leads to a switch of export activities from ACFTA member countries to non-ACFTA member countries.
Conversely, a negative and statistically significant coefficient of FTA_2ijt indicates a decrease in exports from member countries to
non-member countries and is defined as an export diversion effect.