There were 37,000 new loans, worth £3.9 billion - 12% down (19% by value) on the third quarter, and 56% down (65% by value) compared with the fourth quarter of 2007.
The CML only began collecting quarterly buy to let data in 2006, but on the basis of previous half-yearly data this is almost certainly the lowest quarterly lending figure since 2003.
Outstanding buy to let mortgages represented around 10% of all loans, and around 11% of the value of all lending, at the end of 2008.
Over 2008 as a whole, buy-to-let lending accounted for 10.6% of the value of total gross mortgage
advances, down from 12.3% in 2007.
