The Terms tab in the Performance page displays an Averages secondary tab containing average values for the terms in the indexed data.
Median Docs per Term  The median number of documents in which an individual term occurs. 
Mean Docs per Term  The mean number of documents in which an individual term occurs. 
Mean Term Length  The mean length of a term in the database. 
Mean Occurrences per Doc  The mean number of occurrences of terms per document. 
Mean Distinct Terms per Doc  The mean number of distinct terms per document. 
