有勞各位英文高手幫我把以下的句子由中文翻譯成英文！

新客戶帶來未來收入的現值 = Cash income to be bought by new clients.
銷售毛利 = Gross sales profit.
第七年時新客戶的期望銷售量 = Expected sales amount by new clients of the 7th year.
每年維持客戶的成本 = Cost to maintain the customers each year.
折現率 = Cash ratio.
年期之下標 = ??????????
新客戶繼續成為企業顧客的平均年期 = Average years required for a new client become regular.

New customers bring the present value of future income
Sales Maori
The seventh year when sales of new customer expectations
The annual cost to maintain customer
Discount rate
Year under the superscript
Enterprise customers continue to be a new customer, the average year

希望幫到你啦!!^_^