foreign currency exchange rate risk many of our non-u.s .companies maintain both assets and liabilities in local currencies .therefore , foreign exchange rate risk is generally limited to net assets denominated in those foreign currencies .foreign exchange rate risk is reviewed as part of our risk management process .locally required capital levels are invested in home currencies in order to satisfy regulatory require- ments and to support local insurance operations regardless of currency fluctuations .the principal currencies creating foreign exchange risk for us are the british pound sterling , the euro , and the canadian dollar .the following table provides more information on our exposure to foreign exchange rate risk at december 31 , 2008 and 2007. .
[['( in millions of u.s . dollars )', '2008', '2007'], ['fair value of net assets denominated in foreign currencies', '$ 1127', '$ 1651'], ['percentage of fair value of total net assets', '7.8% ( 7.8 % )', '9.9% ( 9.9 % )'], ['pre-tax impact on equity of hypothetical 10 percent strengthening of the u.s . dollar', '$ 84', '$ 150']]
reinsurance of gmdb and gmib guarantees our net income is directly impacted by changes in the reserves calculated in connection with the reinsurance of variable annuity guarantees , primarily gmdb and gmib .these reserves are calculated in accordance with sop 03-1 ( sop reserves ) and changes in these reserves are reflected as life and annuity benefit expense , which is included in life underwriting income .in addition , our net income is directly impacted by the change in the fair value of the gmib liability ( fvl ) , which is classified as a derivative according to fas 133 .the fair value liability established for a gmib reinsurance contract represents the differ- ence between the fair value of the contract and the sop 03-1 reserves .changes in the fair value of the gmib liability , net of associated changes in the calculated sop 03-1 reserve , are reflected as realized gains or losses .ace views our variable annuity reinsurance business as having a similar risk profile to that of catastrophe reinsurance , with the probability of long-term economic loss relatively small at the time of pricing .adverse changes in market factors and policyholder behavior will have an impact on both life underwriting income and net income .when evaluating these risks , we expect to be compensated for taking both the risk of a cumulative long-term economic net loss , as well as the short-term accounting variations caused by these market movements .therefore , we evaluate this business in terms of its long-term eco- nomic risk and reward .the ultimate risk to the variable annuity guaranty reinsurance business is a long-term underperformance of investment returns , which can be exacerbated by a long-term reduction in interest rates .following a market downturn , continued market underperformance over a period of five to seven years would eventually result in a higher level of paid claims as policyholders accessed their guarantees through death or annuitization .however , if market conditions improved following a downturn , sop 03-1 reserves and fair value liability would fall reflecting a decreased likelihood of future claims , which would result in an increase in both life underwriting income and net income .as of december 31 , 2008 , management established the sop 03-1 reserve based on the benefit ratio calculated using actual market values at december 31 , 2008 .management exercises judgment in determining the extent to which short-term market movements impact the sop 03-1 reserve .the sop 03-1 reserve is based on the calculation of a long-term benefit ratio ( or loss ratio ) for the variable annuity guarantee reinsurance .despite the long-term nature of the risk the benefit ratio calculation is impacted by short-term market movements that may be judged by management to be temporary or transient .management will , in keeping with the language in sop 03-1 , regularly examine both quantitative and qualitative analysis and management will determine if , in its judgment , the change in the calculated benefit ratio is of sufficient magnitude and has persisted for a sufficient duration to warrant a change in the benefit ratio used to establish the sop 03-1 reserve .this has no impact on either premium received or claims paid nor does it impact the long-term profit or loss of the variable annuity guaran- tee reinsurance .the sop 03-1 reserve and fair value liability calculations are directly affected by market factors , including equity levels , interest rate levels , credit risk and implied volatilities , as well as policyholder behaviors , such as annuitization and lapse rates .the table below shows the sensitivity , as of december 31 , 2008 , of the sop 03-1 reserves and fair value liability associated with the variable annuity guarantee reinsurance portfolio .in addition , the tables below show the sensitivity of the fair value of specific derivative instruments held ( hedge value ) , which includes instruments purchased in january 2009 , to partially offset the risk in the variable annuity guarantee reinsurance portfolio .although these derivatives do not receive hedge accounting treatment , some portion of the change in value may be used to offset changes in the sop 03-1 reserve. .

Question: what is percentage change in fair value of net assets denominated in foreign currencies from 2007 to 2008?
Answer: -31.7%