Municipal bond sales in the U.S. are set to decrease in the next month while the amount of redemptions and maturing debt falls.

States and localities plan to issue $9.5 billion of bonds over the next 30 days, according to data compiled by Bloomberg. A week ago, the calendar showed $10.7 billion planned for the coming month. Supply figures exclude derivatives and variable- rate debt. Some municipalities set their deals less than a month before borrowing.

North Texas Tollway Authority plans to sell $871 million of bonds, New York State Dormitory Authority has scheduled $690 million, Tennessee State School Bond Authority will offer $459 million and Florida State Department of Transportation will bring $300 million to market.

Municipalities have announced $10.4 billion of redemptions and an additional $8.6 billion of debt matures in the next 30 days, compared with the $22.6 billion total that was scheduled a week ago.

Issuers from California have the most debt coming due with $1.51 billion, followed by Michigan at $1.17 billion and New York with $990 million. Wisconsin has the biggest amount of securities maturing, with $632 million.

Market Shrinks

The $3.6 trillion municipal market shrank by 4 percent in 2014. This year, maturities are poised to drop 38 percent to $176 billion from the 2014 levels.

Investors added $727 million to mutual funds that target municipal securities in the week ended March 25, compared with $194 million in the previous period, according to Investment Company Institute data compiled by Bloomberg.

Exchange-traded funds that buy municipal debt increased by $69 million last week, boosting the value of the ETFs 0.4 percent to $16.6 billion.

State and local debt maturing in 10 years now yields 103.4 percent of Treasuries, compared with 106.3 percent in the previous session and the 200-day moving average of 96 percent, Bloomberg data show.