The tax windfall for corporate America is reshuffling how companies use their cash.
Many companies have opted to spend their tax windfalls on their own shares, as expected, with other options including investments in wages and research.
But meanwhile, fewer companies are lending to the US government by buying Treasurys, and to firms by buying corporate debt.
While the declines are not yet huge, they highlight concerns about where demand for US Treasurys will continue to come from at a time when the US government is driving up spending.
For the corporate bond market, fewer buyers of debt could mop up a source of short-term cash.