“…To our knowledge, there are no studies that analyse the possible presence of interregional spillovers of external shocks of revenue on a local government's efficiency. There is, however, evidence of spillover effects on efficiency at the firm level (Pede, Areal, Singbo, McKinley, & Kajisa, 2018; Skevas & Grashuis, 2019), country level (Adetutu, Glass, Kenjegalieva, & Sickles, 2015; Glass, Kenjegalieva, & Sickles, 2016), regional level (Santolini, 2020; Tsionas & Michaelides, 2016) and local government level (Fusco & Allegrini, 2020; Geys, 2006; Revelli & Tovmo, 2007; Santolini, 2020). This paper focuses on the effect of neighbours' royalties on local efficiency, trying to capture the possibility that more royalties in nearby municipalities affect local equilibrium prices or intermunicipal political competition and thus local efficiency.…”