A reading tells a story; a table states a fact. Here you will find the second kind: the catalogues and scales our calculations rest on, shown as the engine reads them. Nothing is keyed in by hand, and that is the only way to be sure a published table says exactly what a chart applies.
It grows one document at a time. Each is dated by its source, and its page stays put: you can keep it, come back to it, and cite it.