Since the NZ tax in income over $70,000 is 33% that means that she is actually sacrificing 6.7% of her annual salary. It is nothing more than a token. More a public relations stunt than any real sacrifice.
I'm sure she has a higher cost of living than the average worker but a 50% cut in her annual salary would be more realistic and not subject her to any real hardship.
She may be a wonderful politician but like all politicians she is living off the backs of the taxpayer; a sort of symbiotic parasite.