public function increment($field, $step = 1)
    {
        $int = $this->get($field);
        if (is_numeric($int)) {
            $int += $step;
            $this->set($field, $int);

            return $int;
        }

        return null;
    }
public function increment($field, $step = 1)
    {
        $int = $this->get($field);
        if (is_numeric($int)) {
            $int += $step;
            $this->set($field, $int);

            return $int;
        }

        return null;
    }
@param int|string $field Selected field in which the value will be incremented.
@param int|float  $step  Incrementation step.

@return int|float|null Returns the new value or null if the value on $field is not numeric.