def date2per(isodate, rate=2):
    """Returns Year-Period Type-Period Number

    :param isodate:
    :param rate:
    :return:
    """
    stt = '%s%s%s'
    year, month, _ = isodate.split('-')
    if rate not in (1, 2, 3, 4, 6):
        return stt % (year, 1, 1)
    imonth = int(month)
    per = imonth // rate
    rem = imonth % rate
    if rem > 0:
        per += 1
    return stt % (year, rate, per)
