Do not use the endings -st, -nd, -rd or -th with a figure in a date. Note that, in British English, dates are written in the order day–month–year, without internal punctuation.



In British English, the numeric form of the date above is, therefore:



Note that, in American English, dates are written in the order month–day–year, with a comma between the day and the year.



In American English, the numeric form of the date above is, therefore:

• Days of the week
  
  Do not use a comma after the day of the week when it precedes a date.
  
  

  Monday 23 November 2021

  
  
  
• Years
  
  In running text, use all four digits when referring to a year.
  
  

  ’98

  
  

  1998

  
  
  
• Academic years
  
  Write academic years in one of the following two ways, but be consistent. Use a hyphen (-), not an en dash (–).
  
  

  the academic year 2022-2023

  
  

  the 2022-2023 academic year

  
  
  
• Decades
  
  Use numbers to refer to decades rather than writing them out. Do not add an apostrophe before the plural  s.
  
  

  We were all born in the mid-1920s.

  
  
  To refer to decades in the period from 2000 to 2020, use a circumlocution such as the first decade of the 21st century or the second decade of the 21st century.
  
  
• Centuries
  
  Do not use Roman numerals for centuries. Instead, either spell out the century or use the ordinal number.
  
  

  the XX century

  
  

  the twentieth century

  
  

  the XIX century

  
  

  the 19th century

  
  
  
• Festivals and historic events
  
  If a date refers to a festival or historical event, spell out the number.
  
  

  the Fourth of July celebrations

  
  

  the Hundred Years’ War

  
  

  the First of May demonstration

  
  
  
• Laws
  
  In citing pieces of legislation, arrange the dates as shown in the examples below.
  
  

  Spanish Personal Data Protection Law 15 of 13 December 1999

  
  

  Spanish Royal Decree 778 of 30 April 1998

  
  

  Organic Law 4 of 12 April 2007 amended by Organic Law 6 of 21 December 2001 on Universities