C.R.S. § 37-26-114

In the event there shall not be sufficient funds to the credit of a district for the payment in full of an installment of principal or interest when due, the district treasurer shall apply the money in the respective funds in proportionate payments on all bonds or coupons then due, endorsing on the bonds or coupons a notation showing the payments made. After respective maturities, the district treasurer shall make disbursements whenever he has sufficient funds to pay five percent of the total principal or twenty-five percent of the total interest due at maturity.