Extension risk is one of the risk factors of amortizable loan which can lead to the future cash flow and discount change.

延迟风险是抵押贷款的风险因子之一，导致未来现金流和贴现率发生变化。

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You will likely get capital gains treatment and the buyer will have an intangiible asset amortizable over 15 years.

FORBES: Your Money Or Your Life - Which Can You Deduct ?

In the example, the taxpayer incurs an expenditure in 2009 and takes the position that the item is amortizable over a five-year period.

FORBES: Will The 2010 Schedule UTP Provide The IRS 20/20 Hindsight For Prior Tax Years Currently Under Audit?