public function getDateUnitsList()
    {
        return array(
            'S' => $this->translate->_('Seconds'),
            'N' => $this->translate->_('Minutes'),
            'H' => $this->translate->_('Hours'),
            'D' => $this->translate->_('Days'),
            'W' => $this->translate->_('Weeks'),
            'M' => $this->translate->_('Months'),
            'Q' => $this->translate->_('Quarters'),
            'Y' => $this->translate->_('Years')
        );
    }