Here are comparative lists of examples of relative vs. absolute date and time references:
- Absolute: on May 5, 2000; first saturday of August, 1709; 1-1-01; 21:20, 13-02-2006; in 1999.
- Relative: yesterday; several years ago; on May 5; last year.
Note that the main difference between the two types is that relative time reference has to have some origin, or point where to start. For the writer, that origin is the moment of writing, but for the readers this is very inconvenient. Readers have to either find out when the text was written or have to guess. Careful writers would provide the origin for the readers’ convenience, if they opt for relative time/date reference. However, it is much better to use absolute timing. The main reason for this necessity is the dynamic nature of time; the “now” changes every moment. Thus, the writer’s “now” is far earlier than the readers’ “nows”. Even more, the reader’s “nows” are very different. The authors must be careful and think in advance about the readers, addressing to time and date in the absolute form, but not relative to the perpetually-changing “now.”
Even more, careful writers never address to the “now” of writing as present; they address is as it is past, regardless of the writer’s present.
Consider: “As I write this, … ” vs. “When the author was writing this.”
The first example is egoistic, while the second one shows care for the reader, considering the person and the time of access.
Of course, these are only general rules, which are applicable to most cases. However, there are exceptions, when this relative use of time would, for example, project the reader into some event purposefully, to create the feeling of presence, and so on. These cases, however, are rare and must be used only by experienced writers. In 99.6% of cases, however, use absolute time and date reference!
