We certainly have a high Tax to GDP Ratio (I think still the highest). When tax revenues grow at a slower rate than the GDP of a country, the tax-to-GDP ratio drops; when tax revenue grows faster than GDP, the ratio increases. With NZ at the top or constantly in the top 8, it indicates that we have healthy tax growth. Well to me it does, but I am probably wrong lol.
I think a problem with that tax:GDP comparison is that in NZ, healthcare (exception ACC), superannuation, unemployment benefits, are directly funded from consolidated revenue in NZ.
In many countries (comparable social democracies) funding for these may be just as inescapable, but paid for partly or fully by levies taken separately from "income tax".