Manufacturing activity in New York state in February expanded at a slower pace after recording a 20-month high in January, showed a survey released Tuesday by the Federal Reserve Bank of New York. The general business conditions index fell to 4.48 in February from 12.51 in January, which had been the highest reading since May 2012, according to the latest Empire State Manufacturing Survey. The reading was below general market expectations. Among sub-indices, the new orders index fell to -0.21, indicating that orders were about flat, while the shipments index dropped about 13 points to 2.13. However, indexes for the six-month outlook continued to convey fairly strong optimism about future business conditions. The index for expected general business conditions rose to 39.0, and the index for future new orders climbed six points to 45.3, its highest level in two years. The Empire State manufacturing index closely watches manufacturing activity in New York, northern New Jersey and southern Connecticut. The Federal Reserve Bank of New York conducts the survey monthly, and participants represent a variety of industries. Any reading above zero indicates expansion.