Read all CSVs in a directory and do something with them

package.json

{
  "author": "tylor",
  "name": "csv_street_trees",
  "version": "0.0.0",
  "repository": {
    "url": ""
  },
  "main": "trees.js",
  "engines": {
    "node": "~v0.4.9"
  },
  "dependencies": {
    "csv": "0.0.10"
  },
  "devDependencies": {}
}

tree.js

var csv = require('csv');
var fs = require('fs');

var filesFinished = 0;

var diameter = { DIAMETER: 0.00 };
var planted = { DATE_PLANTED: 2012 };
var total = 0;

function test(tree, index) {
  total++;
  if (tree.DIAMETER > diameter.DIAMETER) {
    diameter = tree;
  }
}

function done(count) {
  filesFinished--;
  if (filesFinished <= 0) {
    console.log('Biggest: ' + diameter.DIAMETER);
    console.log('Total trees: ' + total);
  }
}

fs.readdir('./', function readFiles(err, files) {
  var index = files.length;
  while (index--) {
    if (files[index].match(/(csv)$/i)) {
      filesFinished++;
      csv().fromPath(files[index], { columns: true })
           .on('data', test)
           .on('end', done);
    }
  }
});