We used a principal component analysis in acomp geometry (PCA.acomp) to examine variance in the proportions of macronutrients in annual population diets (Aitchison, 1983; Aitchison & Greenacre, 2002; Pawlowsky‐Glahn & Egozcue, 2001). PCA.acomp axes were plotted both within an EMT as curvilinear axes and using a biplot. In PCA.acomp biplots, the length of the link (i.e., distance between arrowheads) along a component relates to the SD of the log‐ratio of two components. Thus, the distance between links is used to evaluate relative variation between components.