Which of the following statements is correct as it relates to changes in accounting estimates? most changes in accounting estimates are accounted for retrospectively. whenever it is impossible to determine whether a change in an estimate or a change in accounting principle occurred, the change should be considered a change in principle. whenever it is impossible to determine whether a change in accounting estimate or a change in accounting principle has occurred, the change should be considered a change in estimate. it is easier to differentiate between a change in accounting estimate and a change in accounting principle than it is to differentiate between a change in accounting estimate and a correction of an error.