BAL Inc reported a net income of $ 200 million on a beginning book value of equity of $ 1.6 billion in 2017. The firm paid out $ 75 million in dividends, and bought back $ 20 million of stock during the year.

Return on equity = 12.5%

- If the reinvestment rate remained at the 2017 level, by how many percentage points did the return on equity have to change in order for the 2018 growth rate to be 10%?