The period–eccentricity (e–﹩{\mathrm{log}}P﹩) distribution of NGC 188 main-sequence binaries. 1σ error bars are shown for all orbits. Triangles represent newly derived orbital solutions, while circles denote previously published solutions. Purple symbols indicate binaries included in the fit to the circularization period, and black symbols show systems excluded from the fit. The solid purple line marks our best-fit circularization function (S. Meibom & R. D. Mathieu 2005), yielding a circularization period of ﹩{P}_{{\rm{circ}}}=14.{4}_{-0.11}^{+0.14}﹩ days.