An ATP Participant's required contribution will be specified in the approval letter. If the ATP Participant's required contribution is specified as a dollar amount and the ATP Participant does not make the required contribution, the ATP Participant shall pay to the CCC in dollars the difference between the amount actually contributed and the amount specified in the approval letter. If the ATP Participant's required contribution is specified as a percentage of the total amount reimbursed by the CCC, the ATP Participant may either return to the CCC the amount of funds reimbursed by the CCC to increase its actual contribution percentage to the required level or pay to the CCC in dollars the difference between the amount actually contributed and the amount of funds necessary to increase its actual contribution percentage to the required level. An ATP Participant shall remit such payment within six months after the end of its program period. The ATP Participant shall make such payment in U.S. dollars, unless otherwise approved in advance by the CCC.