so i was refreshing my understanding of duration so that i can deal with the more complex applications of it

if we have a bond, semi annual with 2 years left,

cf 0.5=5

cf 1=5

cf =1.5

cf 2=105

currently it is selling at 100, so BEV yeild = 5*2=10%

now i am playing around with valuation in excel, just to remaster the basics, if i wanted to calculate the duration of this bond i would shift increase interest rates by 1% by using 5.5 semi annual discounts, and not by using 6% semiannual? cause if i increase the 5 to a 6 the resulting duration is 3.4 which is not correct for a bond that matures in 2 years…