According to figures from Statistics New Zealand released today, car sales are down 19.5 per cent since September 2007.
Fuel sales are also down 2.2 per cent or $14 million.
The significant drops have influenced overall retailsales which dropped 1.3 per cent, or $69 million in October.
However "core retailing", which excludes car sales, fuel sales and the vehicle related industry, rose by 0.8 per cent.
Appliance retail was up 7.6 per cent or $15 million, accommodation was up 5.3 per cent, or $12m, and clothing and soft goods - which covers manchester, linen and textiles - were up 5.5 per cent, or $11m.
But offsetting "core retail" was supermarket sales which were down by 1.2 per cent, or $14m.
Statistician Geoff Bascand said monthly retail sales have had a slight downward trend throughout 2008 with October being 0.9 per cent down when compared to the start of the year.