The template {{As of}} is used to mark potentially dated statements, and will add an article to the appropriate hidden sub-category of Category:Articles containing potentially dated statements. This allows editors to catalogue statements that may become outdated over time. The date used for a given statement should be the date of the most recent reliable source (for currently valid statements), or the date on which the cited reference was produced (for example, when using census data). It should not be used for future dates (use {{update after}} instead). This template should not be substituted.
Usually "as of" is used only in cases where an article is intended to provide the most current information available and will need a future update. It should not be used for historical information that will not change. For example, a mention that the historical "population of Toledo, Ohio, was 13,768 as of the 1860 Census" should not be tagged, as it is a historical fact which will not change. It is appropriate to tag "the population of Toledo as of the 2020 Census was 287,208", as this figure should be updated when a newer census is conducted. The date used for a given statement should be the date of the most recent reliable source(for currently valid statements), or the date on which the data were obtained (for example, when using census figures).
"As of" should not be used with future dates, as it will place the article in nonexistent categories. Instead, use to mark when the next event will occur. Here are two ways to correctly mark statements with future dates:{{Update after}}
Remember to always use precise language when writing about future or current events. The statement should make sense to a reader years into the future, even if the information has changed. If it is possible to predict when a statement will need updating, use the template to indicate when it should be updated. In the above statement the most obvious date is 31 December 2033, after which time construction will have finished or the statement will have become inaccurate. In either case the article should be updated to reflect this.{{Update after}}
When the "as of" phrasing is not ideal, it should be changed to improve encyclopedic prose in either of two ways:
Avoid beginning a series of paragraphs or sentences with repeated instances of the wording "As of", as this can produce a distracting list-like effect. Both "As of" and "Since" can be made lower-case for use in mid-sentence, by addition of the |lc=y parameter, and any use of |alt=... can contain text beginning with lower case.