Density estimation with 95% pointwise CI (blue colors) of the secular frequencies (right column) and their combinations (left column) of the combined solutions from {X_i}, {Y_i}, and {Z_i}, along withthe corresponding values extracted from the La2010d solution (yellow lines), the Newark-Hartford data (redlines; Olsen et al. 2019), and the current values (green lines). The frequencies are obtained by FA over an interval of 20 Myr centered at 210 Myr in the past. The time reference is the time of {Z_i}.