Consider the requirement to report under IFRS.
Should the study necessarily begin in the year in which the relevant data first became available?
And in what year should the study end, other than as might be decided arbitrarily by the researcher to end just as the study is being conducted?
This data availability criterion may be described as a ‘‘constraint.’’
Yet the first year in which the data became available does not necessarily qualify as the appropriate first year of the sample period, and the last year in which the data are still available does not necessarily qualify as the appropriate final year of the sample period.
Suppose, for example, the first one or two years, or the last one or two years, of the period
in which the data were available were of dubious stability because of, say, the passage of major
legislation, the approval of important regulations, the issuance of major amendments to relevant
accounting standards, the withdrawal of relevant accounting standards, the occurrence of a
macro-economic shock, or an increase in managerial actions taken in anticipation of eventual adoption.1