(Bloomberg) -- The municipal bond market is headed for its seventh-straight November of gains, with the US presidential election and a Federal Reserve meeting keeping issuers on the sidelines, while strong investor demand has boosted prices.

Most Read from Bloomberg

• NYC's Underground Steam System May Be Key to a Greener Future

• NYC Gets Historic Push for 80,000 Homes With $5 Billion Pledge

• In Kansas City, a First-Ever Stadium Designed for Women’s Sports Takes the Field

• Trump Promises Could Have Seismic Impact on Washington Economy

• NYC Mayor Adams Names Jessica Tisch to Lead Police Head Amid Probes

Municipal issuance, usually slow in the 11th month, was more muted than usual because state and local governments sought to avoid election-related volatility. Long-term muni bond issuance through Nov. 22 was $23.4 billion, down 6% year-over-year.

Meanwhile, investors typically have more cash on hand from principal and coupon payments than available debt to purchase. This November, demand exceeds supply by $12 billion, according to PGIM. The upshot is that over the past decade, November has tended to be the strongest month of the year, returning 1.1% on average, data compiled by Bloomberg show.

“In November, there’s a healthy amount of reinvestment,” said Jason Appleson, head of municipals at PGIM. “You have technicals that are back in your favor.”

Municipal bonds have posted positive returns in eight of the last 10 Novembers, according to the Bloomberg Municipal Bond Index. December has been even better, with munis gaining 10 years in a row.

This month, long-dated muni bonds have become the most expensive relative to Treasuries in almost three years. Donald Trump’s victory in the presidential election, combined with a Republican sweep in Congress, drove a selloff of US Treasuries, with investors anticipating an inflationary agenda that would likely limit the Federal Reserve’s need cut interest rates much further.

Since mid-September, yields on 30-year US Treasuries have increased about 70 basis points, compared with 14 basis points for 30-year AAA rated municipal bonds with the same maturity. On Thursday, the ratio of 30-year muni-to-Treasury yields fell to 80.4%, its lowest since January 2022.

Barclays Plc analysts led by Mikhail Foux say muni-to-Treasury ratios will likely fall further by the end of the year, meaning munis will get even more expensive relative to US government debt. The market’s favorable dynamics — limited supply coupled with strong reinvestment demand — should support munis in December as it has for the last 10 years in a row.