Also, if you are going to average the numbers, remove the bottom digit as well if you find the top one too anomalous, for more reliable results. (So exclude purple and grey)
Purple / Entropy Nymphs don't use the same mechanism as other nymphs to be selected randomly. That's why they're not included -- not because the number is an anomaly. Actually, given that it's about twice as likely to get a Purple Nymph from the Oracle as any other, the shown amount is expected.