The US dollar's unexpected strength this year has badly affected pension funds, trend-following hedge funds and private investors, although many hedge funds which do not rely solely on following large momentum swings are thought to have recouped most of any losses they may have made whilst selling the greenback. Warren Buffett’s Berkshire Hathaway, too, has been a victim of the dollar's recovery. The investment group’s $21.5 billion of short-dollar forward contracts produced a pre-tax loss of $926 million in the first half of 2005. This was offset, though, by $2 billion profit made from shorting the dollar in the previous three years. It's been a rollercoaster for the dollar this year. Having traded at $1.356 against the euro at the beginning of the year, it strengthened to $1.188 in July, although recently it has fallen back to $1.243. The dollar had fallen 38.7 per cent against the euro in the three years to 2004 over concerns about the US external and budget deficits. Hedge funds, many of which make their profits from identifying and then backing large market trends, made sharp initial losses from the reversal. The BNP Paribas FX Funds Index, which tracks the performance of foreign exchange hedge funds and commodity trading advisers, reported that the sector lost 4.4 per cent in January. The index shows that by June hedge funds had cut year-to-date losses to 1.7 per cent on average after short-term speculators swung to being long on dollars by the spring. These positions have been largely liquidated according to data from the US Commodity Futures Trading Commission.