def qit(fmpp, f0pp, fmf0=4.88):
    """Calculate qIt

    qIt = (fmf0 / ((fmpp / f0pp) - 1)) - 1

    :param fmpp: Fm''
    :param f0pp: F0''
    :param fmf0: Fv/Fm (default: 4.88)
    :returns: qIt (float)
    """

    return (fmf0 / ((fmpp / f0pp) - 1)) - 1