Star formation history of Sco-Cen. Top: age distribution of the 34 clusters in Sco-Cen traces four main star formation events in the history of the association. Bottom: stellar age distribution in Sco-Cen shows a similar pattern. To study the age distribution of clusters and stars, we used a kernel density estimate with an adaptive bandwidth corresponding to the age uncertainty of each sample. The formation of stars and clusters is correlated, but not linearly, meaning that, when compared to the average in the association, more stars were formed per cluster during the peak of star formation rate, about 15 Myr ago.