What do the numbers mean?
From PendorVerse
The most frequently asked question about The Journal Entries (aside from "When is Elf going to write more?") is "What do the numbers on the left side of the table of contents mean?"
They are a date. The idea at the time was to create something that would appeal to fans that expected a "sci-fi"-like dating scheme. Reading the date is straightforward: the first number is a day, the second the year, on the main world and setting for the Journal Entries, Pendor.
Year zero on Pendor is 1884 Terran, and the years are very nearly the same length (source). There are 292 days in a Pendorian year, which eventually becomes the standard calendar of known space. 078 / 01312 Dreamteam Calamities, The Find, for example, happens on the year 3196 CE.
For more information about the Pendorian months and week days, see Pendorian Calendar