Demand for tobacco has fallen 15 per cent at supermarkets since the tax rise in April - a far greater reduction than expected.

"It's extraordinary," public health physician Dr Murray Laugesen said yesterday, commenting on supermarket sales figures supplied to him by research company ACNielsen.

Based on earlier tax increases, a tobacco price rise of 10 per cent would have been expected to reduce sales by 5 per cent.

Has the tax increase detered people from smoking? Here is a selection of Your Views: