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tokens: binaries, CVs, and qLMXBs in the comparison samples. The RS stars also fall in the same region as the SSGs. This overlap with the active binaries hints that heightened chromospheric activity may be responsible for the X-ray activity observed for at least some, and perhaps many, SSG and RS stars. The diminished overlap between the SSG and BY Dra stars (which are also chromospherically active) is due to the generally lower optical luminosities of most BY Dra stars in the comparison samples relative to the SSGs. The X-ray luminosities of the SSGs agree well with both the BY Dra and RS CVn active binary samples. 5.3. Frequency of SSGs across Different Star Clusters Figure 7 shows the number (top panel) and specific frequency (bottom panel) of SSGs as a function of the cluster mass for all clusters with SSGs in our sample. The black symbols in this figure show only the SSGs that are the most probable cluster members and are within our minimum radius completeness limit, and the gray symbols show all SSGs. The Pearson’s correlation coefficient, relating cluster mass and number of SSGs, for the full sample of highly likely cluster members is 0.925. However, this value is large because of ω Cen and 47 Tuc. Excluding these two clusters (the only ones in our sample with masses above 10 6 ) results in a Pearson’s correlation coefficient of −0.278. Furthermore, a test indicates that this limited sample of clusters (still excluding ω Cen and 47 Tuc) is consistent with a flat line at the mean value of SSGs. This result holds even if we include ω Cen and 47 Tuc in this test (using ), with a reduced value of . We conclude that, for this sample, there is no significant correlation between the number of SSGs and the cluster mass. This lack of a correlation in versus results in a clearly visible trend in the bottom panel of Figure 7 : the number of SSGs per unit mass increases toward lower-mass clusters. A test shows that the full sample of SSGs is inconsistent with a flat line at the mean value at very high significance (). The same result holds true for the open and globular clusters individually. The open clusters have a significantly higher specific frequency of SSGs than do the globular clusters. If we take the mean specific SSG frequency for the open clusters of ∼10 −3 −1 and extrapolate that to the globular cluster regime, this would predict about 100 SSGs in a globular cluster with a total mass of 10 5 . The maximum number of SSGs known in any cluster is 19 in ω Cen, followed by eight in 47 Tuc (both of which have masses ). A hint of this trend was also noted by Cool et al. ( 2013 ) in comparing their ω Cen SSG sample to those in M67 and NGC 6791. This is now verified with the larger sample of SSGs studied here, and we discuss the implications of this result in Section 6 . 5.4. Summary of Demographics We conclude that the SSG region has an elevated frequency of variable stars and X-ray sources relative to stars of similar luminosities in the normal