CNBC » Municipal bonds are expected to be considerably scarcer in 2018, with one firm projecting a “steep decline” in issuance. Rising yields are raising costs for governments, while changes in tax laws have made munis less appealing. Already, January issuance fell 26 percent from the same period in 2017 and dropped 57 percent from December, which along with November saw a huge rush ahead of new tax laws taking effect.