Our operating income is adversely affected when we incur certain contract costs or certain increases in contract costs that cannot be billed to customers. Contract cost growth has occurred and may occur in the future when expenses to complete a contract increase and/or differ materially from our initial estimates. Factors that have caused, and may in the future cause, contract cost growth include, but are not limited to, inflation, technical challenges, manufacturing difficulties, delays, workforce-related issues, including labor shortages and reduced productivity, changes in the nature and complexity of the work performed, the timeliness, availability and cost of materials or equipment, subcontractor performance or product quality issues, performance delays, availability and timing of customer funding, changes in trade policy, and natural disasters. A significant increase in contract costs from our original cost estimates on one or more contracts could have a material adverse effect on our financial position, results of operations, or cash flows. For example, our results for the year ended December 31, 2024, were adversely affected by significant challenges relating to labor availability, our supply chain, and inflation, among other challenges. We cannot clearly predict how long these challenges will continue, whether these challenges will change over time, or whether our actions to address these challenges will be successful.
Our risk varies and our ability to recover costs on contracts with our U.S. Government customers depends upon the type of contract under which we are performing: firm fixed-price, fixed-price incentive, cost-type, or time and material. See the Contracts section under Management's Discussion and Analysis of Financial Condition and Results of Operations in Item 7 for descriptions of the types of contracts that comprise our business.
Approximately 48% of our revenues in 2024 were generated under fixed-price incentive contracts, approximately 47% were generated under cost-type contracts, approximately 2% were generated under time and material contracts, and approximately 3% were generated under firm fixed-price contracts. Fixed-price contracts generally tend to have more financial risk than cost-type contracts, including as a result of inflationary pressures, wage pressures and labor shortages, and supplier challenges. These contracts increase the risk that we may not recover all of our costs or will generate less profit or a loss if our costs exceed initial estimates. With cost-type contracts, allowable costs are generally subject to reimbursement plus an award or incentive fee, which is uncertain and may be earned over time. Under each type of contract, our operating results could be adversely affected if we are unable to control costs, particularly if we are unable to negotiate an increase in contract price, or recover increased costs, with our customers.
U.S. Government contracts often extend for years, and unforeseen events, such as technology difficulties, fluctuations in the price of raw materials, a significant increase in or sustained period of higher inflation, supplier issues, including equipment delays, challenging labor market conditions, unexpected rework, and cost overruns, have in the past resulted, and may in the future result, in contract prices becoming less favorable or even unprofitable to us over time. Higher interest rates resulting from inflationary pressures can also impact the fair values of our contracts. Moreover, if we fail to meet contract deadlines or specifications, we may be required to renegotiate contracts on less favorable terms, be forced to pay penalties or liquidated damages, or suffer major losses if the customer exercises its right to terminate.
Cost overruns have adversely impacted, and may continue to impact, our results of operations, which are dependent on our ability to maximize our earnings from our contracts. This risk would be greater if our contracts shifted toward a greater percentage of fixed-price contracts, particularly firm fixed-price contracts. Cost overruns or the failure to perform on existing programs also may adversely affect our ability to retain existing programs and win future contract awards. In addition, changes in contract financing policy for fixed-price contracts, such as changes in performance and progress payments policies, could significantly affect the timing of our cash flows.
From time to time, we may begin performance under an undefinitized contract action with a not-to-exceed price prior to completing contract negotiations, in order to support U.S. government priorities. Uncertainties relating to final contract price, specifications and terms, or loss of negotiating leverage associated with contract definitization, may negatively affect our profitability.