Four indistinguishable layers of figures: design rules for information systems used to plan and monitor internal oversight

An annual oversight plan holds figures that look alike but are not. Some state what was planned, some what was actually carried out, some how much was paid, and some how the results were assessed. All four are routinely mixed in one file with nothing to tell them apart, so a question as simple as "has this assignment started?" cannot be answered without asking the person responsible. This note calls the problem four indistinguishable layers of figures. It argues that the four merge not through carelessness but because the medium offers no place to keep them separate. A spreadsheet has no layers, does not record who entered a figure and when, and has to serve three rhythms of change that are out of step with one another. From there the note sets out five design rules that any inspectorate can use when building or assessing its oversight planning tools, without requiring any particular technology. The note states the rules, not the results of testing them. A before-and-after measurement is under way, and its results will be reported separately. The note also sets out the limits of its own claims. The note does not name any audited entity, assignment letter number, audit result, or individual's data. This is an English translation of the Indonesian original, "Empat lapis angka yang tidak terbedakan" (version 1.1, https://doi.org/10.5281/zenodo.22762121). The record holds two files with the same content: a PDF for reading and citing, and the Markdown (.md) source text, included so that other institutions can easily copy it and adapt it into their own guidance under the CC BY 4.0 licence.