The Treasurer of State shall apply the prudent investor rule while serving in a fiduciary capacity for State Treasury Money Management Trust participants. The prudent investor rule means that in making investments, the fiduciaries shall exercise the judgment and care under the prevailing circumstances that an institutional investor of ordinary prudence, discretion, and intelligence exercises in the management of large investments entrusted to it, not for speculation but for investment, considering the permanent disposition of funds, and the probable safety of capital as well as probable income.