A company's ROA and ROE are constant as 4% and 12% respectively and these two variables are defined as net income dividend by the previous year's total assets and equity respectively. The company always pays out 50% of its net income as dividend. What is the maximum growth rate in firm size (total assets) if the source for asset increase is retained earnings and additional debt that keep the debt ratio constant. (please report the answer as a decimal number and keep THREE decimal places such as 0.018)?