When in borderline hyperinflation, the GDP number is meaningless.
Also, a shrinking economy with normal inflation is better than a growing economy with hyperinflation, because that second is never really growing, just the meaningless number is going up.
The inflation calculation is the one that doesn't get the inflation correctly into account. That's because it always have errors, and those errors grow more than linearly with the inflation rate.
Also, a shrinking economy with normal inflation is better than a growing economy with hyperinflation, because that second is never really growing, just the meaningless number is going up.