Learn Hardcore Spanish (Spain): El ejercicio fiscal falta, de ahí que revisemos los datos fiscales. - The tax year is missing, which is why we check the tax data.

Breakdown of El ejercicio fiscal falta, de ahí que revisemos los datos fiscales.

Why is revisemos in the subjunctive instead of revisamos?

Because de ahí que normally introduces a clause in the subjunctive.

So:

This is a very common pattern:

If you wanted the indicative, Spanish would usually choose a different connector, such as:

So the subjunctive here is not random; it is triggered by de ahí que.

What exactly does de ahí que mean?

It means something like:

It links the first clause to the consequence in the second clause.

In this sentence:

the idea is:

The fiscal year/accounting period is missing; that is why we review the tax data.

It is a fairly formal connector, especially common in written or administrative language.