contrib.sh

#!/bin/sh
git log --numstat | awk '/^Author: /{author=$0} /^[0-9]+\t[0-9]+/{n = $1 + $2; d[author] += n; t += n} END { for(a in d) { printf("%6d  %6.3f%%  %s\n", d[a], d[a] * 100 / t, a)}}' | sort -rn

# written less illegibly, it is:
#
# git log --numstat | \
#   awk '
#     /^Author: /{author=$0}
#     /^[0-9]+\t[0-9]+/{n = $1 + $2; d[author] += n; t += n}
#     END { for(a in d) { printf("%6d  %6.3f%%  %s\n", d[a], d[a] * 100 / t, a)}}
#   ' | sort -rn