Indiana Code Title 30. Trusts and Fiduciaries § 30-2-15-25

(1) net income is insufficient to pay the unitrust amount, the unitrust amount shall be considered to have been paid from net realized short term capital gains;

(2) net income and net realized short term capital gains are insufficient to pay the unitrust amount, the unitrust amount shall be considered to have been paid from net realized long term capital gains;  and

(3) net income and net realized short term and net long term capital gains are insufficient to pay the unitrust amount, the unitrust amount shall be considered to have been paid from the principal of the trust.