Commodity prices have slumped this market with oil the biggest mover of the major international commodities.

See weekly market update video below with IRG BOP's Jonathan York.

It dropped below US$91 on the New York Mercantile Exchange on Monday – a change brought about, in part, by a rising US dollar.

The NZ dollar has dropped against it, almost dropping back down under the 80c threshold after it hit a record high 81.71c on Friday.