#!/bin/bash


echo "#	tot	diff	dir"
ls -1dr 20* | tr . " " | 
  date -f - +%s | 
  while read a; do 
    day=$a
    [ -z "$last" ] && first=$day && last=$day
    d=$(date -d @$day +%Y%m%d.%H%M)
    echo $[ ($first - $day) /86400]"	"$[ -($day - $last) /86400]"	"$d; last=$day; lastd=$d
  done | cat -n
