Today, due to regression of population distribution to the city center triggered by low birthrate and aging, not only small-and-medium-sized private railways in local areas, but private railways in big cities are gradually having more lines connecting the city center and suburbs, whose transportation volume is changing from increase to decrease.
現在では少子化・高齢化と人口分布の都心回帰が進み、地方中小私鉄だけでなく、大都市圏の私鉄でも、都心と郊外を結ぶ路線については輸送人員が増加から減少に転じる路線も出てきている。