Posterior for the first percentile (χ _eff,1%) of the χ _eff distributions implied by each of our component spin models, as shown in the right-hand column of Figure 5. The median values and 90% credible intervals for χ _eff,1% are also reported in Table 1. Each of our component spin models require the binary black hole population to contain spins misaligned by more than 90° relative to their Newtonian orbital angular momentum. Correspondingly, χ _eff,1% is inferred to likely (although not necessarily) be negative. The χ _eff,1% values recovered here are consistent with the minimum χ _eff values measured by Abbott et al. (2021a, 2021b).