def PVT(df, price='Close', volume='Volume'):
    """
    Price Volume Trend
    Returns: list of floats = jhta.PVT(df, price='Close', volume='Volume')
    Source: https://www.fmlabs.com/reference/default.htm?url=PVT.htm
    """
    pvt_list = []
    for i in range(len(df[price])):
        pvt = 0
        if i > 0:
            pvt = pvt_list[i - 1] + df[volume][i] * (df[price][i] - df[
                price][i - 1]) / df[price][i - 1]
        pvt_list.append(pvt)
    return pvt_list
