13) How many balance sheets are required by IAS 1 when there is a change in accounting policy and why? 14) Give an example of a change in accounting policy which does not require retrospective treatment and explain why? 15) Why is the retrospective approach conceptually appropriate for changes in accounting policy? 16) How should enterprises reflect changes in accounting standards? 17) What are two reasons why an accounting change may be permitted to give modified retrospective or prospective treatment?