def _sum_frts(results:dict):
    """
    Get total number of FRTs

    Arguments:
        results {dict} -- Result set from `get_total_frts`
    Returns:
        int -- Total number of FRTs in the nation
    """
    if results == None:
        return 0

    total_frts = 0

    for result in results:
        if result['state_total']:
            total_frts += result['state_total']

    return total_frts