# Key Performance Indicators for Food Supply Chain: A Bibliometric and Systematic Literature Review
## 1 Introduction
In chronological order, the first review of KPIs for FSC was by [PERSON] and [PERSON] [19], who analyzed how a pre-requisite program and KPIs for food safety can be developed for the production of fresh produce, in both low-input and high-input supply chains. [PERSON] et al. [20] provided a critical literature summary concerning the assessment of product water footprint, to map the state-of-the-art research related to freshwater consumption and pollution in the agricultural and industrial sectors. Moreover, the authors proposed a first-effort hierarchical decision-making framework that includes water footprint mitigation policies for agri-FSCs in order to support all stakeholders in developing a comprehensive water stewardship strategy. The review developed by [21] aimed at emphasizing the benefits of implementing Industry 4.0 in the agri-FSC. In particular, the authors presented how technologies enhance agri-FSC development, and then, they identified and highlighted the most common challenges that Industry 4.0 implementation faces in the agri-food environment. Finally, [PERSON] et al. [22] realized a comprehensive understanding of different social innovation measures adopted for decreasing food waste, utilizing a systematic literature review (SLR). The authors concluded that social innovation activities such as food rescue hubs, digital food-sharing platforms, solidarity stores, and social supermarkets are widely deployed in different food waste reduction processes. However, to the best of the authors' knowledge, a review covering all the key aspects of performance measurement in the FSC is still missing, and this was the original gap intended to be filled by the present study. This work, in fact, originates from a previous one [23], in which a gap was highlighted, namely that of KPIs for the FSC. In the manuscript at hand, accordingly, the authors propose an update of the literature and of the previous taxonomy, aimed at integrating the results presented in [23], by analyzing a wider stream of research. In more detail, this research focuses on the following research questions (RQs):  
* **RQ1. How is the research on KPIs for the FSC characterized? ** This question aims to discuss the statistical trend of research related to the targeted topic, in terms of temporal evolution and publication type; research methodology; source (i.e., journals publishing the document in question); geography of the documents (i.e., where the study was carried out); top cited papers; and most prolific authors. * **RQ2. What are the most frequent and persistent topics over time, and how do they relate to main research themes? ** This question aims to map the research topics; that goal is obtained by analyzing the papers' keywords with respect to their frequency and persistence. To be more effective, the timespan of analysis is divided into four periods; with respect to the same periods, an analysis of the evolution of the main topics is also conducted. Keyword co-occurrence is finally used to look at the relationships between the research topics identified. * **RQ3. How can KPIs for the FSC be classified? Which different products have been predominantly studied? What FSC processes and activities are covered by KPIs? ** This question, overall, is intended to provide an exhaustive mapping of the literature about KPIs in the FSC. More precisely, the question concerns the different products treated in the FSC (and their trend in time), the distribution of KPIs and papers by FSC processes and activities, and the trend of publications by KPI categories. A final framework is also proposed for addressing this RQ, so as to let emerge the most common KPIs for each stage of the FSC, including a classification depending on the nature of the final products managed.