Rates held steady Thursday as mixed economic data had little impact on mortgage-backed securities. This morning, weekly Jobless Claims fell to 344,000, well below forecast. Fourth Quarter GDP was revised slightly higher, to +0.1% from -0.1%, although an increase to 0.5% had been expected. The Chicago Purchasing Managers Index rose to 56.8, beating expectations. Readings above 50.0 indicate expansion in the manufacturing sector for the Midwest region. No other key data will be released today.