By John S. McClenahen In January of this year, U.S. construction spending fell off its torrid pace of the second half of 2003. The U.S. Commerce Department estimates spending at an annual rate of $931.2 billion in January, three-tenths of a percentage point less than its revised figure of $934.4 billion for December. An increase in the pace of highway and other kinds of public construction was more than offset by a decrease in residential and other private construction. Spending on private construction was at an annual rate of $715.8 billion in January, 0.5% below the December's $719.3 billion rate. Public construction in January was at an annual rate of $215.4 billion, 0.2% higher than December's $215.1 billion rate.