Mrs Tanner never thought she'd leave Christchurch, but the earthquakes were unsettling her daughters Ruby, 3, and Clara, 19 months.
"After June we decided the girls had had enough."
They said goodbye to their family and friends and, like many others, crossed the Tasman to Melbourne.
The Tanners said they had settled into their new apartment and were positive about job opportunities in their new city.
They don't know how long they will stay but believe they made the right choice.
"We'd still be in Christchurch if it wasn't for the earthquakes," Mrs Tanner said.
Statistics NZ manager Deb Potter said the 2.4 per cent population drop was the result of departures outnumbering arrivals by 10,600, partly offset by more births than deaths.
This is the first official figures on of population change in Christchurch since the Canterbury earthquakes.
For some parts of the country, population growth accelerated as people moved from earthquake-affected areas.
The five areas with the fastest rate of population growth in the year to June were Selwyn, Queenstown-Lakes, Ashburton, Waimakariri and Hurunui.
In many parts of the country, population growth slowed as an increase in international migrant departures was only partly offset by an inflow of people from the earthquake-affected areas.
A decision on the future of Christchurch Cathedral, which was crippled in the February 22 quake, will be announced soon by by the Anglican Church.
Senior church figures have refused to comment on speculation the Gothic-style building will be demolished.
The 120-year-old cathedral withstood violent earthquakes in 1881, 1888, 1922, 1901 and on September 4 last year.
Engineers have been in talks with the church over whether it can be rebuilt on its current site or will require demolition.
Cathedral dean the Very Rev Peter Beck said yesterday that no decision had been made but confirmed: "There will be a formal announcement made on the decision of the future. It won't be very far from now.
"It's a really complex process. It has involved broad and wide discussions with all sorts of people.
"We've had to have expert analysis and technical reports, and all of this has been done very carefully because it's obviously a very significant time that we are in.
"Safety is our first priority and a final decision will not be made until we've got all the information, reports received by the church and the options and ramifications are all considered.
"It's really important for us that we make the right decision for the future, for the church, but also for the city and wider community."
While the city awaits a decision, Christchurch Central MP Brendon Burns hopes the population will have a say on its future.
"My fervent wish is that the community is given the widest possible chance for consultation on this issue. There would be a lot of tears if it had to come down."
