In the 1960s, long-term studies of the future that forecasted the development of a country became fashionable in the Western world. Whereas certain countries prioritized a multidisciplinary approach, in which both economic development and social change were taken into account, others only considered the development of economic variables and in particular economic growth. The Perspektivstudien, which projected the future of Switzerland 30 years ahead, focused solely on the economic development of the country, implicating that political events had no impact on economic development in the long run. This contribution traces back the conceptualization of the economy as a separated sphere that was inherent to the Perspektivstudien and investigates the historical context in which they were created. This chapter shows that to understand the emergence of those studies, Keynesianism has to be taken into account as a governmentality in which the idea of a macroeconomic controllability prevailed. Furthermore, the contribution suggests to conceptualize those long-term forecasts not as mere descriptions of possible outcomes, but as performative economic knowledge that invented an a-historical future.