When managing fields for a content type, fields of type "list (integer)" can't be shared? In the drop-down for "add existing field" not all fields are available for reuse. Specifically I would like to reuse a field of type "list (integer)" because I will be adding 300 of them to my content type with exactly the same settings (just different labels and machine names). Doing  the manually is going to take me over eight hours since it takes about 1.5 min to add a field and configure it's settings. Is it possible to reuse fields of type "list (integer)"?

Thanks!!

ps: if you are unsure what I mean by reusing a field see here: Documentation for Field-UI and look at the section titled, "Reusing Fields".
Here's the answer to this question:

I cannot use the same field within one content type. Only one instance of a field may be used within each content type. This is why the field which I have created is not showing up in the drop-down for "add existing field" - it is not available.