hyphenation - Does "cost-benefit ratio" use a hyphen or an en-dash?

Should I write "cost-benefit" (hyphen) or "cost–benefit" (en dash), and why?

Answer

Formally, hyphens are for joining terms, and en dashes are for ranges and distinctions. En dashes have a secondary application joining terms that are already hyphenated or contain spaces, but that doesn't apply here. In this situation I would use an en dash or a slash. Of course, if you do write it with a hyphen, nobody is going to be confused.

Technically, cost–benefit analysis can be interpreted as either [cost–benefit] analysis—an analysis of costs versus benefits—or cost–[benefit analysis]—costs versus an analysis of benefits. Luckily, the latter doesn't make any sense and would really only arise from deliberate pedantic misinterpretation.