A system for maintaining consistency of a data value using a probability includes an interface and a processor. The interface is configured to receive a data value for storing. The processor is configured to store the data value in a data element of a data structure and determine, using an adaptive filter, a probability of certainty associated with the data value. The probability of certainty associated with the data value depends on a time since the data value was updated. The adaptive filter provides as output the probability of certainty and store the probability of certainty associated with the data value in the data structure.