Maybe it's not used in your part of the world, but it's #6 on this list by Andreessen Horowitz: http://a16z.com/2015/08/21/16-metrics/ http://a16z.com/2015/08/2

Maybe it's not used in your part of the world, but it's #6 on this list by Andreessen Horowitz: http://a16z.com/2015/08/21/16-metrics/ http://a16z.com/2015/08/21/16-metrics/