Your second line should be , since it's being compounded over 3 semiannual periods (18 months).

Similarly, the multiplier in your 5th line should be (1 + 0.115/2), as you're dealing with one 6-month compounding period.

In both the 7th and 10th lines, there are 6 one-month compounding periods, so your multiplier on both of these lines should be .

Give that a spin and check back in with what you've got.