Do you know the first activity a statutory auditor performs on a financial statement before actually starting to audit it?

They check whether the closing balances of the previous year match with the one reported on the previous financial statement. This a good way to get the point raised from this principle: you should always verify that the data shown within your reports is consistent within them and if needed also with external sources.

Let's say, for instance, you have a table showing a three cases A, B, and C found in a population, which sums up to 1,436 cases. You then show in two separate tables how cases A and C can be further split into subclusters. A check you should always do is that the total shown within these two tables is consistent with the one shown as a raw total in the first table.

Missing these checks, which could also appear as trivial, and sharing documents with inconsistent data, will dramatically decrease the level of trust in your analyses and thus increase the effort needed to convince your stakeholders of the validity of your results.