Cities with forking paths? Agglomeration economies in New Zealand 1976–2018
利用新西兰134个地点1976-2018年的微观数据，研究发现集聚经济在1991年达到峰值后下降约1个百分点，2006年后保持稳定；大城市在生产上有净优势但消费上没有，而靠近大城市的小地点集聚经济更强。
We consider whether external urban economic advantages (agglomeration economies) vary with time and space using detailed micro-data on 134 locations in New Zealand for the period 1976–2018. We find subtle temporal variation, with estimates of agglomeration economies peaking in 1991 and then falling by approximately 1 percentage point in the subsequent 15-years. Since 2006, however, estimates have remained broadly stable; the world has not been getting “flatter”. Our results reveal more significant spatial variation: Large cities offer net benefits in production but not consumption, whereas small locations close to large cities (“satellites”) experience agglomeration economies that are stronger than average.