Group By Count Using awk

count.awk

find . -name 'message-*.csv' -exec wc -l {} \; | awk -F'[[:space:]-]' '
  NR == 1 { print; next }
  { 
    id = $3;
	qty = $1;
	if (qty < 289) {
		reads[id] = qty;
	}
  } END {
    for (r in reads) {
		qty = reads[r];
		printf "%-15s\t%s\n", r, qty | "sort -rnk2";
	}
  }
'