<div class="pie">20%</div>
<div class="pie">60%</div>
<div class="pie animated">0%</div>

.pie {
	width: 100px;
	height: 100px;
	display: inline-block;
	margin: 10px;
	transform: rotate(-90deg);
}

svg {
	background: yellowgreen;
	border-radius: 50%;
}

circle {
	fill: yellowgreen;
	stroke: #655;
	stroke-width: 32;
}

@keyframes grow { to { stroke-dasharray: 100 100 } }

.pie.animated circle {
	animation: grow 2s infinite linear;
}

function $$(selector, context) {
	context = context || document;
	var elements = context.querySelectorAll(selector);
	return Array.prototype.slice.call(elements);
} 

 $$('.pie').forEach(function(pie) {
	var p = parseFloat(pie.textContent);
	var NS = "http://www.w3.org/2000/svg";
	var svg = document.createElementNS(NS, "svg");
	var circle = document.createElementNS(NS, "circle");
	var title = document.createElementNS(NS, "title");
	
	circle.setAttribute("r", 16);
	circle.setAttribute("cx", 16);
	circle.setAttribute("cy", 16);
	circle.setAttribute("stroke-dasharray", p + " 100");
	
	svg.setAttribute("viewBox", "0 0 32 32");
	title.textContent = pie.textContent;
	pie.textContent = '';
	svg.appendChild(title);
	svg.appendChild(circle);
	pie.appendChild(svg);
});