Former U.S. Treasury Secretary Lawrence Summers said on Thursday that the Federal Reserve's decision to significantly slow down the pace of shrinking balance sheet this week actually sent a worrying signal that there is a problem with market demand for long-term federal debt."This should arouse people's alarm and be regarded as a disturbing trend," Summers said in an interview on TV program. He pointed to the move as a sign that Fed policymakers believe that "the market absorption capacity of long-term bonds is limited."The Federal Reserve announced on Wednesday that it will lower the upper limit on the amount of U.S. Treasury Bond that will not be reinvested after maturity from $25 billion per month to $5 billion starting in April. While Powell said the immediate trigger for policymakers