Entity/OrderElement.php
public function setDuration($duration)
    {
        $this->duration = $duration;

        $data = array(
            0 => 1,
            1 => 1,
            2 => 1.9,
            3 => 2.7,
            4 => 3.2,
            5 => 3.6,
            6 => 3.8,
            7 => 4,
            8 => 4.5,
            9 => 5,
            10 => 5.5,
            11 => 6,
            12 => 6.5,
            13 => 7,
            14 => 7.5,
            15 => 7.9,
            16 => 8.3,
            17 => 8.7,
            18 => 9.1,
            19 => 9.5,
            20 => 9.9,
            21 => 10.3,
            22 => 10.6,
            23 => 10.9,
            24 => 11.2,
            25 => 11.5,
            26 => 11.8,
            27 => 12.1,
            28 => 12.4,
            29 => 12.7,
            30 => 13,
        );

        return $this->setLocationCoeff($data[$duration]);
    }
public function setDuration($duration)
    {
        $this->duration = $duration;

        $data = array(
            0 => 1,
            1 => 1,
            2 => 1.9,
            3 => 2.7,
            4 => 3.2,
            5 => 3.6,
            6 => 3.8,
            7 => 4,
            8 => 4.5,
            9 => 5,
            10 => 5.5,
            11 => 6,
            12 => 6.5,
            13 => 7,
            14 => 7.5,
            15 => 7.9,
            16 => 8.3,
            17 => 8.7,
            18 => 9.1,
            19 => 9.5,
            20 => 9.9,
            21 => 10.3,
            22 => 10.6,
            23 => 10.9,
            24 => 11.2,
            25 => 11.5,
            26 => 11.8,
            27 => 12.1,
            28 => 12.4,
            29 => 12.7,
            30 => 13,
        );

        return $this->setLocationCoeff($data[$duration]);
    }
Set duration

@param integer $duration
@return OrderElement