Missing data statistics (not installed by default)
 coefficient_of_variation geomean meansq skewness
 covm cor cov corrcoef harmmean median statistic
 detrend kurtosis moment std mad naninsttest nantest 
 nansum nanstd normpdf normcdf norminv meandev mod rem
 percentile quantile rankcorr ranks rms sumskipnan 
 var mean sem spearman trimean tpdf tcdf tinv zscore