Related Clues:

• Vital statistic
• Segment of history
• Fete, e.g.
• MLB statistic
• Get old
• Grow sharper, perhaps
• Survey datum
• FDR's time in office, e.g.
• The Wild West, e.g.
• Wisk alternative
• Geologi-cal time
• Chronology component, perhaps
• Span
• It's a big stretch
• Ripen, say