These fields report the total tax factoring in any refundable credits, as well as the effective rate of the next $1,000 of ordinary income and capital gains, respectively. Unlike the marginal bracket for ordinary income, the effective rate is calculated as the incremental amount of tax divided by $1,000 for the two different types of income. 
Because the addition of income may result in the phase out, phase in, or elimination of deductions, credits and other taxes, the effective rate may differ significantly from the anticipated marginal rate. This is best illustrated by looking at the Range Calc screens.
You can also click on the question mark icons for more detail on what these figures mean and to review the math behind the numbers. Note that these fields only contain information for scenarios generated in Scenario Analysis, and not from any scenarios based directly on the uploaded return.