Histograms of the periods (above) and inclinations (below) of the NLs in this paper, according to their class(es). The period gap (Knigge 2006) is indicated in the upper panel. Note that in the two panels of each figure the NLs are the same, but divided according to their class. To avoid confusion the histogram bins for each pair of classes have been plotted on either side of the central values, with sizes that avoided contact between adjacent bins.