We sliced the 4-dimensional CO2 emissions data of GTAP into 132 (=66*2) 
2-dimensional data matrices for easy reading purposes. 
The original CO2 emissions data is of the format:
ECO2(EGY_COMM,SRC,EMITERS,REG).
The 2-dimensional CO2 emissions matrices are stored in gtapco2.xls.
Tags of the excel sheets are 4-character named, according to the following system:
The first 3 characters correspond to the GTAP country code. 
For example, "arg" refers to Argentina.
The fourth character is either "d" or "m", with "d" referring to domestic, and "m"
referring to imported.

January 10, 2003
