Definitions:
a number expressing the central or typical value in a set of data, in particular the mode, median, or (most commonly) the mean, which is calculated by dividing the sum of the values in the set by their number

the apportionment of financial liability resulting from loss of or damage to a ship or its cargo.

constituting the result obtained by adding together several amounts and then dividing this total by the number of amounts

amount to or achieve as an average rate or amount over a period of time; mean