# Key Performance Indicators for Food Supply Chain: A Bibliometric and Systematic Literature Review
## 3 Results
### Outcomes of the Content Analysis
With respect to the supply activity, as can be seen from the figure above, the combination of multiple activities appears to be the most investigated with reference to the use of KPIs, with 8 out of 20 contributions, followed by the growing activity (6 papers). Figure 12, instead, shows the classification for production, i.e., the industrial level. There are 91 studies for this area, 66 of which focus on the area of production alone, while the others study production along with other areas (25 papers). Specifically, production and supply with 10 studies, production and distribution with 11 papers, and production with supply and distribution with 4 contributions, with the same meanings provided for the supply stage. In this case, four activities can be found, plus the combination option: performance evaluation, planting, processing, and harvest. As depicted in the figure above, processing is the main activity in the production area (49 studies), followed by combinations of several activities within the same paper (29 publications). Interestingly, only one study focused on harvesting activity. Figure 13, finally, reports the classification for the distribution. There are 41 papers on this area, 25 of which focus on the area of distribution alone, while the others focus on the  
Figure 11: Distribution of reviewed papers by supply activities. Figure 12: Distribution of reviewed papers by production activities. distribution along with other areas (16 papers): distribution with supply and production (4 studies), distribution and supply (1 study), and distribution with production (11 papers). Distribution in the FSC is mainly characterized by two activities: transport (34 papers) and retail (2 studies). In addition, it can be seen from the figure that there are five studies that combine these two activities together. This result is definitely in line with the sustainability issue; indeed, transport is one of the most impactful activities in terms of harmful emissions toward the environment, and several companies are starting to measure their emissions and to monitor their transport activities [74]. Therefore, it is not surprising that several studies have their focus on that. As already mentioned in Table 2, the KPIs were classified into three categories of sustainability, including economic, environmental, and social aspects. Figure 14 shows the time distribution of KPIs classified into the three categories, again including the combination and the documents in which this information is not detectable. As can be seen from the figure above, the combination of more than one category of KPIs prevails (92 out of 125 studies--73.6%), followed by the economic perspective with  
Figure 14: Trend of publications by KPI categories. Figure 13: Distribution of reviewed papers by distribution activities. 21 papers, 8 papers for which the information was not available, 2 documents in which KPIs for measuring the environmental perspective are mentioned, and only 1 including the social dimension. Indeed, the most investigated FSC stage was production, and according to this, economic KPIs are closer to the industrial context. Moreover, it is once again demonstrated that quite often social perspective is neglected since it is difficult to be quantified and measured [74]. Among the economic KPIs, we found Return on assets [71; 75], Gross margin [76], Return on sale [68], Economic farm surplus [38], and Sharpe ratio [77]. Among the environmental KPIs, we identified Water footprint [76], pH levels [78], CO\({}_{2}\) emissions [21; 56; 51], Global Warming Potential [79], and Soil fertility [38]. Finally, among those classified with the social dimension were Labor relations [37], Human equity [80], and Accessibility of basic services [38]. Given the high quantity of studies with KPIs combinations, Figure 15 details the different groupings.