Apostrophe – Why is it “Old 97’s” and not “Old 97s”? Are the Old 97’s confused about the rules of grammar? No. “Do any of you have Webster’s grammar books? If you do, look up the section on apostrophes. You will find that it’s OK, in order to prevent confusion, to add an apostrophe before an ‘s’ when making something plural. For instance, if Johnny comes home from school and says, ‘I got two F’s today in attitude’, then he’s at least right grammatically. It would be confusing if he said, ‘Fs’. Get it? So five years ago we decided to invoke the rule and be ‘Old 97’s’ rather than ‘Old 97s’. Or ‘Old Nine-Seven-Ess’, as we would have probably be called. If you have ever seen our original demo, you’ll probably notice that we were ‘The Old 97’s’. I don’t remember why we changed. We just did.” – Ken Bethea (1998)

From The Old 97’s Glossary Page