U.S. INTERVENED TO AID DLR IN JANUARY, FED SAYS U.S. authorities intervened in the foreign exchange market to support the dollar on one occasion during the period between the start of November 1986 and the end of January, the Federal Reserve Bank of New York said in a report. The Fed's quarterly review of foreign exchange operations said that the U.S. bought 50 mln dlrs through the sale of yen on January 28. This operation was coordinated with the Japanese monetary authorities and was funded equally by the Fed and the U.S. Treasury. The Fed's intervention was on the morning after president Reagan's State of the Union message and was "in a manner consistent with the joint statement" made by U.S. Treasury secretary James Baker and Japanese finance minister Kiichi Miyazawa after their January 21 consultations. At that meeting, the two reaffirmed their willingness to cooperate on exchange rate issues. The Fed's report did not say at what level the intervention occurred. But on January 28, the dollar closed at 151.50/60 yen after dipping as low as 150.40 yen earlier in the session. It had closed at 151.05/15 yen the previous day. The dollar had plumbed a post-World War II low of 149.98 yen on January 19 and reached a seven-year low of 1.7675 marks on January 28. It ended that day at 1.7820/30 marks. The Fed noted that, after trading steadily throughout November and the first half of December, the dollar moved sharply lower until the end of January. It closed the three-month review period down more than 11 pct against the mark and most other Continental currencies and seven pct lower against the yen and sterling. It had fallen four pct against the Canadian dollar. During the final days of January, pressure on the dollar subsided. Reports of the U.S.-Japanese intervention operation and talk of an upcoming meeting of the major industrial countries encouraged expectations for broader cooperation on exchange rate and economic policy matters, the Fed said. Moreover, doubts had developed about the course of U.S. interest rates. The dollar's swift fall had raised questions about whether the Fed would let short-term rates ease. Thus the dollar firmed to close the period at 1.8320 marks and 153.70 yen. According to the Fed's trade-weighted index, it had declined nine pct since the beginning of the period. The dollar had risen as high as 2.08 marks and 165 yen in early November. The Fed last intervened in the foreign exchange market on November 7, 1985 when it bought a total of 102.2 mln dlrs worth of marks and yen. The Fed's action followed the September 1985 Plaza agreement between the five major industrial nations under which they agreed to promote an orderly decline of the dollar.