The effective cost of the collar
purchased on 1 January for 30 June expiration = ($130,000 – $100,000)[1 +
(0.05 + 0.02)(180/360)] = $31,050.
Effective total amount of loan = $60,031,050 (我记得应该是 loan - FV premium costs = net amount borrowed)所以我最后求 EAR 是除以 60,000,000 - 31,050 ? 不知道是不是官方给的答案错了?
Put payoff = $60,000,000[max(0,0.0450 – 0.0600)](180/360)
= $0
Call payoff = –$60,000,000[max(0,0.0600 – 0.0600)](180/360)
= $0
Interest on loan = $60,000,000[0.06 + 0.02](180/360)
= $2,400,000
Effective rate = [(60,000,000 + $2,400,000)/($60,031,050)]365/180 –
= 8.16%