The median asking rent for rental homes advertised on Trade Me Property rose by 5% last year.

However there were significant differences between the main centres, with asking rents rising strongly in Auckland, modestly in Wellington and declining strongly in Christchurch.

In Auckland the median asking rent was $495 a week in December, down slightly from $500 a week in November but up 7.6% compared to December 2014.

The biggest increases in Auckland were for apartments, up 7.1% compared to a year earlier while asking rents for stand alone houses posted more modest gains of less than 6% for the year (see table below).

In Wellington the median asking rent for all types of properties was $410 a week in December, up 3.8% compared to December 2014.

Townhouses posted the strongest gains for the year in Wellington, with their median asking rent climbing to $450 a week which was up 12.5% on a year earlier, while asking rents on apartments in the capital were unchanged from a year earlier.

The market definitely appears to have moved in favour of tenants in Christchurch, where asking rents were well down on where they were 12 months previously.

The median asking rent for all types of properties in Christchurch was $420 a week in December, which was down 6.7% on a year earlier.

Townhouses led the fall, with their median asking rents declining by 10.6% between December 2014 and December 2015 while asking rents on 3-4 bedroom houses declined by 7.2% over the same period.

The head of Trade Me Property, Nigel Jeffries, said rents had plateaued over the last 12 months.

"When looking at New Zealand's median asking rent trend over the last five years, the rental market has clearly plateaued over the last 12 months," he said.

A similar trend occurred in in 2011 and 2012, before rents started rising again in 2013 and 2014, he said.

However the Christchurch rental market continued to weaken as it recovered from the Canterbury earthquakes and rebuilding work brought more homes to market.

"Median weekly rents are down 6.7% in the Garden City and we are not any signs of a halt at this point," Jeffries said.