def squared_pov_index(expenditure, poverty_line):
    """
        This is a weighted sum of poverty gaps, where the weights are the proportionate poverty gaps. 
        Hence, by squaring the poverty gap index, the measure implicitly puts more weight on observations that fall well below the poverty line.
        
        First argument is a list having numerical values of individual's or country's expenditure
        Second argument refers to the minimum income for not being considered as poor.
    """
    index = 0
    for country in expenditure:
        if country < poverty_line:
            index += (poverty_line - country) / poverty_line * ((
                poverty_line - country) / poverty_line)
    if len(expenditure) != 0:
        return index / len(expenditure)
    else:
        print('Check Expenditure data.')
        return
