The weighted average dollar exchange rate with tomorrow settlements amounted to RUR29.31, down RUR0.08 against the official dollar rate set for December 16. This has been the fourth sag in the dollar rate in a row. As reported earlier, on December 10 to 15 the US dollar lost a total of RUR0.16. Commercial bank dealers attribute these developments to the Central Bank gradually lowering its bid for dollars. According to experts, the bank was buying dollars in large volumes at RUR29.3850. They say that yesterday the bank purchased at least $1bn, and therefore it is much more restrained on the currency market today. The Central Bank's bid for dollars is now hovering at about RUR29.30.