Municipals Weekly: The return of 10% munis

September flash PMI data came in well above expectations, reinforcing a "no-landing" narrative and boosting markets' expectations for additional Fed tightening. Rates sold off sharply, with the Treasury curve bear-flattening and 10yr and 30yr yields rising toward peak levels last seen in 2007. Munis also weakened, with AAA yields nearing recent highs and the 10s30s curve flattening to 109bp, though ratios remained stable and credit spreads tightened. The muni tax exemption's value continued to rise, reaching 312bp as of 23 September;