This excerpt taken from the HPQ 10-Q filed Mar 11, 2010.
CONSTANT CURRENCY PRESENTATION
Revenue from our international operations has historically represented, and we expect will continue to represent, a majority of our overall net revenue. As a result, our revenue growth has been impacted, and we expect will continue to be impacted, by fluctuations in foreign currency exchange rates. In order to provide a framework for assessing how each of our business segments performed excluding the impact of foreign currency fluctuations, we present the year-over-year percentage change in revenue performance on a constant currency basis, which assumes no change in the exchange rate from the prior-year period. This constant currency disclosure is provided in addition to, and not as a substitute for, the year-over-year percentage change in revenue on an as-reported basis.