Electronic Article Date fields?

I’m perplexed by the Date fields offered in Endnote for Electronic Articles:

I understand “Date Accessed”, but why is there no “Date Posted”?

And why is “Date Cited” a field?  

Should i add a new field for  “Date Posted” or perhaps i should be listing my reference as a different reference type?

Thanks for any help

Steve Freeman
Center for Organizational Dynamics      
University of Pennsylvania