How much slower is Array.concat compared to Array.push

concat_vs_push.js

const Benchmark = require("benchmark");
const _ = require("lodash");
const suite = new Benchmark.Suite();

const TIMES = 10000;
suite
  .add("pushing", function () {
    const docs = [];
    for (let i = 0; i < TIMES; i++) {
      docs.push(new Date());
    }
  })
  .add("concat", function () {
    let docs = [];
    for (let i = 0; i < TIMES; i++) {
      docs = docs.concat(new Date());
    }
  })
  .on("cycle", function (event) {
    console.log(String(event.target));
  })
  .on("complete", function () {
    console.log("Fastest is " + this.filter("fastest").map("name"));
  })
  // run async
  .run({ async: true });