Very few of the tablets are complete, and some are in an extremely fragmentary state. Where no date formula survives, it is often possible to date them based on the astronomical observations recorded. The surviving tablets range in date from the mid-7th to the 1st century BCE, but the vast majority date between 400 and 60 BCE. Diaries usually cover periods of four to six months, divided into monthly sections. Daily astronomical observations form the bulk of each section. At the end of each month, the Diaries report the river level of the
Euphrates; the market exchange values of several commodities in Babylon, and sometimes selected historical events such as warfare, disease outbreaks, visits from kings or officials, and cultic activities. The Diaries contain no explicit indications of purpose, but since they exhibit significant parallelism with
prognostic material, it is likely that they were connected to some extent with
divination. There are also parallels in content and phrasing between the Diaries and the
Late Babylonian Chronicles. In addition to the evidence they offer about Babylonian astronomy, the Diaries are the main contemporary source for the political history of Late Achaemenid and
Hellenistic Babylonia, while their records of commodity values provide exceptionally detailed and extensive economic data. ==Notable entries==