Computed spiral pattern speed for the Scutum, Sagittarius, Local, and Perseus Arms (from left to right). Solid dots show the first column in Table 2, corresponding to a 10−50 Myr interval. The transparent dots are for the rest of the columns. The shaded violin plots in the x-axis show the distribution of R_G for the OCs in the 10−50 Myr interval. The dotted line shows the circular velocity from the Milky Way rotation curve. The estimated Ω_p values show a decreasing trend with galactocentric radius.