public function testGetPercentageOfDropouts()
{
$total = 100;
$num = (int) rand(1, 50);
$expected = round(($total - $num) / $total * 100, AnalyticsExport::PERCENTAGE_PRECISION);
$this->assertInstanceOf(AnalyticsExport::class, $this->instance->setStarts($total));
$this->assertEquals($total, $this->instance->getStarts());
$this->assertInstanceOf(AnalyticsExport::class, $this->instance->setCompletions($num));
$this->assertEquals($num, $this->instance->getCompletions());
$this->assertEquals($expected, $this->instance->getPercentageOfDropouts());
}