In text, describe a range using prepositional phrases, such as “between X and Y” or “from X to Y.” You may also join the beginning and end of a numerical range or span of years with a hyphen or en dash, but make sure you don’t include the prepositions.
When indicating a span of years with a hyphen or en dash, either drop the first two digits of the second year or keep all four. Whatever you do, stay consistent. If the years span a century change, always use all four numbers of the second year.
Right: Between 2000 and 2010, revenue dropped 15 to 20 percent.
Right: From April to August, the exhibit drew 400–500 visitors per week.
Right: We’re open Monday through Friday.
Right: 1979–81, 1979–1981, 1979–2002
Wrong: Jerry Trickie was the associate athletics director for communications between 2013–15.
Wrong: 2009–’12, ’09–’12
If the range occurs outside a sentence, such as in a heading, advertisement or flier, a hyphen or en dash is often preferable. Depending on design, adding a single space to each side of the hyphen or en dash can improve appearance and readability.
Right: Monday – Friday, Sept. 14–22, Sept. 14 – Oct. 5, 30–50 percent