Formulas for calculating food self-sufficiency ratios in previous studies and author comments

The food self-sufficiency ratio of each country is obtained by dividing the amount of food production by the amount of food supply, but this is not the only way to calculate the food self-sufficiency ratio. Before starting the calculation, issues such as the food to be calculated, the unit of measurement of food and its data source, and the calculation method for primary and secondary products must be resolved. We summarized how major previous studies have addressed this issue. The author of this document selected 20 studies that contain specific descriptions from previous studies on this issue. The author then added comments to all previous studies. The main comment was that although the formula for calculating the food self-sufficiency ratio of each country is incomplete, there is a large amount of valid previous research that contains many suggestions.