The complexity of a country's product mix is related to its economic growth. This paper extends this key insight from the economic growth literature to the second half of the 19^th century, by reconstructing Revealed Comparative Advantages (RCA) and Economic Complexity Indices (ECI) for tens of polities, including both independent countries and colonies. It does so by exploiting product-polity information from the catalogues of five universal exhibitions, held in Paris in the second half of the 19^th century (1855, 1867, 1878, 1889, 1900). For this period, exhibition data are available at a more disaggregated level than export data, on which RCA and ECI are typically based. This is the first application of ECI to the pre-Second World War era. A significant relation is observed between ECI, the level of GDP per capita, and the latter's long-run growth. Furthermore, the evolution of RCA and ECI reveals processes of structural change and economic development, notably the emergence of Germany and Switzerland, which developed along the technological paradigms of the second industrial revolution and thus attained positions of technological and economic primacy.

一个国家产品组合的复杂性与其经济增长有关。本文通过重建包括独立国家和殖民地在内的数十个政体的显示比较优势 (RCA) 和经济复杂性指数 (ECI)，将这一关键见解从经济增长文献扩展到 19 世纪^{下半叶。它通过利用 19世纪}下半叶在巴黎举行的五个世界性展览目录中的产品政策信息来做到这一点世纪（1855、1867、1878、1889、1900）。在此期间，展览数据比出口数据更细分，RCA 和 ECI 通常以此为基础。这是 ECI 首次应用于二战前的时代。在 ECI、人均 GDP 水平和后者的长期增长之间可以观察到显着的关系。此外，RCA 和 ECI 的演变揭示了结构变化和经济发展的过程，特别是德国和瑞士的出现，它们沿着第二次工业革命的技术范式发展，从而获得了技术和经济的首要地位。