Prices for New Zealand's main commodities fell to a 1 1/2-year low in September, led by an ongoing fall in dairy products, while prices for beef hit a record high, ANZ Bank's commodity price index showed on Thursday. The index fell 1.3 percent from August, plumbing its lowest since March 2013 and posting its seventh consecutive monthly decline. The biggest falls were seen in skim milk powder, which fell to its lowest level since June 2012 as the continued fall in global dairy prices sent the overall price index of dairy products to its lowest in nearly two years.