For an historical comparison:
Over the time you have held your properties, calculate what the taxable return was and compare that with the estimated capital gain on your equity invested.
Compare that with the capital gain and taxable income on a similar investment over the same period in (say) the listed kiwi Properties (KPG) or any other blue chip listed company.
As for the future - any capital gains tax that may be introduced may also be applied to an investment in a listed company.
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