By: Mark Glennon*   The Stanford Institute for Economic Policy Research recently published a splendid new database, Pension Tracker, that includes “market based” numbers on state and local pension debt. For Illinois, the numbers (linked here) are simply astounding.   Pensions, governments and reporters use “actuarial based” numbers, which are built on assumptions typically set by politically appointed pension trustees. Those assumptions include, most importantly, high earnings expectations for pension investments — the “discount rate” — typically, about 7.5% —  which no reputable financial economist accepts. Pension Tracker shows those numbers and also “market based” numbers, for which it