Possible Clues:

• Listed alphabetically
• Linked to, eg, CPI
• Like many reference books, in the back matter
• Related to the cost of living
• Like stocks and almanacs
• Independent? Old edition is put in list
• Certainly including vote that's systematically listed
• Given a key vote, sure to hold it
• I assure you, holding variable but protected against inflation
• Without vote, but certainly on the register