A widely watched index shows American home prices dropped by the sharpest annual rate on record in January.

The Standard & Poor's/Case-Shiller 20-city housing index released Tuesday tumbled by a record 19 per cent from January 2008.

It was the largest decline since the index started in 2000. The 10-city index dropped 19.4 per cent, also a record.

All 20 cities in the report showed monthly and annual price declines.

Prices in the 20-city index have plummeted 29 per cent from their peak in summer 2006, while the 10-city index has fallen 30 per cent.

Prices are at levels not seen since late 2003.