Methods, systems, and vehicles are provided for retaining data in a vehicle. In various embodiments, the vehicle includes a sensor, a processor, and a memory. The sensor is configured to sense an aspect of the vehicle. The processor is configured to receive data from the sensor, sample the data at a first rate and retain the data at a second rate that is less than the first rate while the vehicle is in operation. The memory is in communication with the processor, and includes a plurality of storage locations each identified with a unique address. The processor is further configured to determine a current storage location address for a latest sample of the data at the first rate such that older samples of data are retained at the second rate less frequent than the first rate while the vehicle is in operation.