Hashparty add hours column and "per hour" caption to payments

hashparty-add-payments-hours.js

//PASTE THIS TO BROWSER CONSOLE(F12) AND EXECUTE(ENTER)
//RESULT: https://pasteboard.co/H0vltKF.jpg
var payments = [];

$('#payments_rows').find('tr').each(function(){
    var $tr = $(this); 
    var dateStr = $tr.find('td').first().html().replace(/,/g, ''); 
    var amountStr = $tr.find('td:nth-child(3)').first().html();
    payments.unshift({date: new Date(dateStr), amount: parseFloat(amountStr), el: $tr});
})


var totalHours = 0,
	totalAmount = 0;

payments.forEach(function(pay, index){
	var hoursEl = null;
	if(!pay.el.find('.hours').length)
		hoursEl = pay.el.append('<td class="hours"></td>');
	
	hoursEl = pay.el.find('.hours').first();

	if(!index)
		return;

	var prevPay = payments[index-1];
	var timeStampDiff = Math.round((pay.date.getTime() - prevPay.date.getTime())/1000);
	var hoursCount = Math.round((timeStampDiff/3600) * 100)/100;
	
	totalHours += hoursCount;
	totalAmount += pay.amount;
	
	hoursEl.html(hoursCount);
});
if(!$('.yourStats table th.hours').length)
	$('.yourStats table thead tr').append('<th class="hours">Hours</th>');

$('.stats h4.yourStats').text('Payments (' + (Math.round(totalAmount/totalHours * 100)/100) + ' per hour)');