En base a la siguiente definición

What is the Look-back Calculation?
In simple terms, the look-back calculation is a calculation of additional interest that needs to be paid to (or refunded by) the IRS on taxes paid on contract revenue that has been recognized in prior years.

The look-back calculation, which only applies to completed long-term contracts (contracts open more than 12 months), compares the percentage of gross profit that was recognized in prior years to the actual gross profit percentage once the job has been completed. Based on that analysis, the calculation determines whether or not the gross profit for that particular job was “over” or “under” reported in prior years based on job cost estimates at the time of the tax filings. If gross profit was overstated in the past due to changes in estimates or job fade, then theoretically, income was overstated and too much tax was paid in the prior year and the taxpayer is entitled to have interest refunded to them on that excess tax.

Clear as mud, right? Unfortunately, the vice versa is also true. If profit was understated due to conservative estimates or job pick up, you may end up paying Uncle Sam some interest.

Como lo defines aqui debe ser asi, es el tecnisismo utilizado

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Note added at 12 days (2009-10-04 15:42:06 GMT)
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