#!/usr/local/bin/bash
SIZE=86566 # page size
COUNTER=1
DOWNLOAD=$(< size)
while :
  do wget -O /local/file http://address.tld/ &>/dev/null
  echo "Downloaded $(echo "scale=3; $DOWNLOAD/1048576" | bc) megabytes"
  let COUNTER=COUNTER+1
  let "DOWNLOAD=DOWNLOAD+(SIZE*COUNTER)"
  echo $DOWNLOAD > size
done