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I was trying to calculate the duration in the inbuilt function "BOND" given in the new texas BA II pls pro. Here is the question: $1000 Par, 4% semiannual, 10 years to maturity, 6% yield.. In case using the formula =( V(-20bps) - V(+20bps))/(2*V(0)*delta Y) gives the result 7.93 But now...