NEW YORK, Feb 3 Speculators reduced bullish bets on the U.S. dollar for a fourth straight week, as net longs fell to their lowest since late October, according to data from the Commodity Futures Trading Commission released on Friday and calculations by Reuters. The value of the dollar's net long position totaled $18.47 billion in the week ended Jan. 31, down from $20.04 billion the previous week. The U.S. currency has slumped this year, undermined by the Trump administration's weak dollar rhetoric, driving its worst January performance in three decades. This week was no exception as the dollar continued to trend lower, posting its largest weekly percentage fall in more than six months. A smaller-than-expected rise in U.S. wage growth as seen in Friday's U.S. non-farm payrolls report for January has dampened the outlook for the dollar as well. The data suggested that there was still some slack in the labor market that would keep inflation in check, likely slowing the pace of U.S. rate hikes by the Federal Reserve this year. "The U.S. dollar is likely to be pressured further, as it has been since the beginning of the year, as the promise of accelerated Fed tightening fades for the time being," said James Chen, head of research at Forex.com in Bedminster, New Jersey. CFTC data also showed net short contracts on the Japanese yen fell to 58,331, the lowest since early December. The yen's moves, especially on Friday, have been mostly dictated by the Bank of Japan's action. The BoJ on Friday announced plans to buy an unlimited amount of 5-10 year Japanese government bonds to "hit CPI target as soon as possible," said BoJ Governor Haruhiko Kuroda. "The (Japanese) central bank's actions are negative for JGBs and negative for the yen and will be a factor that helps keep dollar/yen supported," said Kathy lien, managing director of FX strategy at BK Asset Management in New York. Net shorts on the Mexican peso, meanwhile, continued to fall and in the latest week touched their lowest since late December. The Mexican peso has been the most sensitive to U.S. President Donald Trump's comments about immigration and trade policies, falling to record lows against the dollar a few weeks ago. The peso, however, has since recovered as investors bought back the currency on the view that the worst was behind it. It has been one of the best-performing currencies against the dollar since Trump's inauguration on Jan. 20, rising about 8 percent. The Reuters calculation for the aggregate U.S. dollar position is derived from net positions of International Monetary Market speculators in the yen, euro, British pound, Swiss franc and Canadian and Australian dollars. Japanese Yen (Contracts of 12,500,000 yen) $6.465 billion Jan. 31, 2017 Prior week week Long 32,216 27,127 Short 90,547 93,967 Net -58,331 -66,840 EURO (Contracts of 125,000 euros) $6.168 billion Jan. 31, 2017 Prior week week Long 125,689 131,904 Short 171,402 184,252 Net -45,713 -52,348 POUND STERLING (Contracts of 62,500 pounds sterling) $4.856 billion Jan. 31, 2017 Prior week week Long 42,232 51,521 Short 104,004 114,693 Net -61,772 -63,172 SWISS FRANC (Contracts of 125,000 Swiss francs) $2.166 billion Jan. 31, 2017 Prior week week Long 6,812 6,198 Short 23,952 19,842 Net -17,140 -13,644 CANADIAN DOLLAR (Contracts of 100,000 Canadian dollars) $-0.267 billion Jan. 31, 2017 Prior week week Long 44,939 36,175 Short 41,467 33,656 Net 3,472 2,519 AUSTRALIAN DOLLAR (Contracts of 100,000 Aussie dollars) $-0.914 billion Jan. 31, 2017 Prior week week Long 59,187 54,552 Short 47,131 44,258 Net 12,056 10,294 MEXICAN PESO (Contracts of 500,000 pesos) $1.517 billion Jan. 31, 2017 Prior week week Long 26,000 32,133 Short 89,208 96,787 Net -63,208 -64,654 NEW ZEALAND DOLLAR (Contracts of 100,000 New Zealand dollars) $0.075 billion Jan. 31, 2017 Prior week week Long 32,712 25,851 Short 33,734 35,734 Net -1,022 -9,883 By Gertrude Chavez-Dreyfuss (Reporting by Gertrude Chavez-Dreyfuss; Editing by Tom Brown) Source:Reuters