Cumulative contribution of different k values to $C_{\mathit{ij}}^{\mathit{XY}}(\ell )$ for a given ℓ in the nearest redshift bin (ij = 00). Left: Case of WL, XY = LL. Right: Case of GC, XY = GG. For each ℓ, 99.5% of the contribution stands below the black isocontour. In the pessimistic case, we include all values of (ℓ,k) on the left of and below the dashed grey lines in the calculation of our observables; in the optimistic case, on the left and below the dashed orange line. Thus, we always include at least 99.5% of the contribution to each $C_{\mathit{ij}}^{\mathit{XY}}(\ell )$.