A section setting method comprising: collecting fuel efficiency information over a plurality of fuel-efficiency-information-collecting sections (s1 to sn), which is information related to fuel efficiency of a vehicle that travels from a starting point to a destination point and is obtained under a plurality of types of vehicle operations together with location information of the vehicle at each time; wherein fuel-efficiency-change patterns of each driver are collected by a control center in routes that are identical or similar to one another for each of the fuel-efficiency-information-collecting sections (s1 to sn) and characterized by comparing change patterns in the collected fuel efficiency information for each of the location information; connecting change pattern sections, which are parts of the change patterns, sequentially from the starting point to the destination point based on a result of the comparison; and setting, as a section to be used for calculation of optimal fuel efficiency, a section that is obtained by dividing a route at positions corresponding to connection points of the connected change pattern sections such that a first optimal fuel-efficiency-change pattern is obtained by sequentially connecting the portion of the first fuel-efficiency-change pattern (Lfa) by a first driver (Da) in a first set section between a starting point (Ps) and a first point (Pa), the portion of a second fuel-efficiency-change pattern (Lfb) by a second driver (Db) in a second set section between the first point (Pa) and a second point (Pb), and the portion of the first fuel-efficiency-change pattern (Lfa) by the first driver (Da) in a third set section between the second point (Pb) and a destination point (Pg). collecting fuel efficiency information over a plurality of fuel-efficiency-information-collecting sections (s1 to sn), which is information related to fuel efficiency of a vehicle that travels from a starting point to a destination point and is obtained under a plurality of types of vehicle operations together with location information of the vehicle at each time; wherein fuel-efficiency-change patterns of each driver are collected by a control center in routes that are identical or similar to one another for each of the fuel-efficiency-information-collecting sections (s1 to sn) and characterized by comparing change patterns in the collected fuel efficiency information for each of the location information; connecting change pattern sections, which are parts of the change patterns, sequentially from the starting point to the destination point based on a result of the comparison; and setting, as a section to be used for calculation of optimal fuel efficiency, a section that is obtained by dividing a route at positions corresponding to connection points of the connected change pattern sections such that a first optimal fuel-efficiency-change pattern is obtained by sequentially connecting the portion of the first fuel-efficiency-change pattern (Lfa) by a first driver (Da) in a first set section between a starting point (Ps) and a first point (Pa), the portion of a second fuel-efficiency-change pattern (Lfb) by a second driver (Db) in a second set section between the first point (Pa) and a second point (Pb), and the portion of the first fuel-efficiency-change pattern (Lfa) by the first driver (Da) in a third set section between the second point (Pb) and a destination point (Pg).