Consolidate loans

How Is The %26ldquo;average Account Age%26rdquo; In The Equifax Credit Report Calculated?
I have a combination of Open, Closed, Revolving, Consolidated and unConsolidated student loans, and a couple credit cards I have never used. I have averaged these in many different ways but have not yet arrived at the %26ldquo;Average Account Age%26rdquo; that is reported in the Equifax credit report. For those who haven't purchased their report, an %26ldquo;average account age%26rdquo; is given, and the longer it is, the better for one's credit score. Hopefully someone who has a simpler credit history can shed some light on h