JS calculator of fleet size & age. You need to be a member, though

flightradar24

// go to https://www.flightradar24.com/data/airlines/<airliner>/fleet and run on console

const planes = [];
const tables = document.querySelectorAll('.table-condensed');
tables.forEach(table => {
	let tbody = table.querySelector('tbody');
	let trs = tbody.querySelectorAll('tr');
	trs.forEach(tr => {
		let age = parseInt(tr.querySelector('td:last-child').innerText, 10);
		if (isNaN(age)) {
			age = 0;
		}
		planes.push(age);
	});
});

var average = arr => arr.reduce( ( p, c ) => p + c, 0 ) / arr.length;

console.log('fleet size: ', planes.length);
console.log('fleet average age: ', average(planes));

List of all airliners