Preferred stock valuation calculator, valuation, something, learning, instead

Mechanic

hi all,
CFA Vol 5, Reading 60, page 277. (first 6 lines on the page)
FV = 20
PMT (D) = 2
N = 12
I/Y = 4.1
CPT PV, i get 36.76, instead of the 31.01 in the text. my calculator is in the "END" mode. what am i missing, pls?
i get 36.6 for the annual payment, instead of 30.84.
am i confused? am i learning too much to miss something very easy?