US/Others government bond coupon frequency

Context = calcul of the dollar safety margin in contingent immunization

When no indication is given, should one assume that the frequency of the coupon is 6 months?

For actualisation purpose, if given a target final value FV in N years, the initial portfolio value required to reach FV should be :

FV/(1+ bond equivalent yield/2)^(2*N)

or could it be

FV/(1+bond equivalent yield)^N ?


ok thks