My phrase is: "The main (indexes / indicators) of regional development".
Which noun should I use?
I have searched for any difference in their meanings on the Internet, but didn't find anything certain.
From my point of view (and I suppose it may be totally wrong), an indicator is something what tells us about the presence or absence of something, and nothing more. If so, then as my (indexes / indicators) are all different numbers (different values, not just "present" or "absent"), should I use the word "indexes", not "indicators"?
I will be very grateful for your help.