Looks like it. I put your 151,000 in my spreadsheet and came up with the same result of 11,880. So it looks like Turbo Tax is doing it the same as me. Yes it is 6 % per person. On a joint return the phaseout is calculated separately for each person, so the 6% phases out $6,000 for each person.
Figure it out by hand the same as me on IRS Schedule 1-A
