From 1 October 2015, the Parliament introduced some changes to the property rules called as Bright-line test. The purpose of the test is to reduce the number of foreign speculators on NZ property and thus maintain positive housing prices of big cities in New Zealand. This rule only applies to residential properties bought on or after 1 October 2015. The idea behind the test is that taxpayer has to pay tax on the gain when you selling your property (with some exceptions). By taxing on the gain, it somewhat discourages speculators for housings as the profit is not as good as before.