The referendum in question is the Indigenous Voice to Parliament referendum in Australia. The referendum was defeated, with a "no" majority called by the ABC in at least four states, and a projected percentage of 55% of votes across the country. The Constitution can only be changed if there is a double majority, meaning there must be a national majority of voters across all states and territories and a majority of voters in a majority of the states (at least four of the six states). The defeat of the referendum means that a federal advisory board to parliament including Aboriginal and Torres Strait Islander People will not be enshrined in the constitution. The result was declared quite early in the evening, with Tasmania being the first state to be declared as a "no" state, followed by New South Wales and South Australia. The referendum cost an estimated $450 million, and there will be no change to the constitution.