Sex;Social class;Average number;Total BOTH SEXES;Total;Average;7.80 BOTH SEXES;Total;Standard deviation;1.69 BOTH SEXES;I;Average;7.77 BOTH SEXES;I;Standard deviation;1.66 BOTH SEXES;II;Average;7.81 BOTH SEXES;II;Standard deviation;1.67 BOTH SEXES;III;Average;7.75 BOTH SEXES;III;Standard deviation;1.63 BOTH SEXES;IV;Average;7.77 BOTH SEXES;IV;Standard deviation;1.70 BOTH SEXES;V;Average;7.80 BOTH SEXES;V;Standard deviation;1.70 BOTH SEXES;VI;Average;7.79 BOTH SEXES;VI;Standard deviation;1.72 BOTH SEXES;No data recorded;Average;8.23 BOTH SEXES;No data recorded;Standard deviation;1.93 MALES;Total;Average;7.86 MALES;Total;Standard deviation;1.65 MALES;I;Average;7.65 MALES;I;Standard deviation;1.55 MALES;II;Average;7.78 MALES;II;Standard deviation;1.60 MALES;III;Average;7.83 MALES;III;Standard deviation;1.62 MALES;IV;Average;7.80 MALES;IV;Standard deviation;1.63 MALES;V;Average;7.87 MALES;V;Standard deviation;1.68 MALES;VI;Average;7.95 MALES;VI;Standard deviation;1.62 MALES;No data recorded;Average;8.84 MALES;No data recorded;Standard deviation;1.93 FEMALES;Total;Average;7.74 FEMALES;Total;Standard deviation;1.73 FEMALES;I;Average;7.89 FEMALES;I;Standard deviation;1.76 FEMALES;II;Average;7.83 FEMALES;II;Standard deviation;1.73 FEMALES;III;Average;7.68 FEMALES;III;Standard deviation;1.63 FEMALES;IV;Average;7.73 FEMALES;IV;Standard deviation;1.78 FEMALES;V;Average;7.72 FEMALES;V;Standard deviation;1.71 FEMALES;VI;Average;7.66 FEMALES;VI;Standard deviation;1.79 FEMALES;No data recorded;Average;7.87 FEMALES;No data recorded;Standard deviation;1.83