MicrobeCensus enables accurate quantification of gene family abundance. Each plot shows the median abundance of essential single-copy genes across 84 stool samples from the HMP. (A) Gene family abundance was computed using relative abundance, which is scaled so the abundance of all genes sums to 1.0 for each sample. (B) Gene family abundance was computed using RPKG (reads per kilobase per genome equivalent). RPKG leverages estimates of AGS made by MicrobeCensus to normalize gene family abundance values.