The 20 dollar difference was my mistake when I made an incorrect entry.
I thought my spouse's Pension income was also incorrect.
Please note that my Pension which was split shows the amount in the detailed tax summary with no split. Adjacent to and on the same line, my spouse's pension income is shown augmented by the split. By showing my pension income unchanged it gives the impression that my spouse's income should be the original (non-augmented) amount. There is a deduction several lines down showing the reduction in my pension.
There is no error in Turbo tax from this perspective.