public function testCustomRangePreviousNEndToday()
 {
     $range = new Range('range', 'previous3');
     $correct = array(date('Y-m-d', time() - 86400 * 3), date('Y-m-d', time() - 86400 * 2), date('Y-m-d', time() - 86400 * 1));
     $this->assertEquals(count($correct), $range->getNumberOfSubperiods());
     $this->assertEquals($correct, $range->toString());
 }