Principal Financial Group, Inc.  Notes to Consolidated Financial Statements — (continued) 5.
Derivative Financial Instruments — (continued) The fair value of our derivative instruments classified as assets and liabilities was as follows:
## Table 0 ##
(1) The fair value of derivative assets is reported with other investments on the consolidated statements of financial position.
(2) The fair value of derivative liabilities is reported with other liabilities on the consolidated statements of financial position, with the exception of certain embedded derivative liabilities.
Embedded derivative liabilities with a fair value of $6.6 million and $23.6 million as of December 31, 2010 and 2009, respectively, are reported with contractholder funds on the consolidated statements of financial position.
Credit Derivatives Sold When we sell credit protection, we are exposed to the underlying credit risk similar to purchasing a fixed maturity security instrument.
The majority of our credit derivative contracts sold reference a single name or reference security (referred to as ‘‘single name credit default swaps’’).
The remainder of our credit derivatives reference either a basket or index of securities.
These instruments are either referenced in an over-the-counter credit derivative transaction, or embedded within an investment structure that has been fully consolidated into our financial statements.
These credit derivative transactions are subject to events of default defined within the terms of the contract, which normally consist of bankruptcy, failure to pay, or modified restructuring of the reference entity and/or issue.
If a default event occurs for a reference name or security, we are obligated to pay the counterparty an amount equal to the notional amount of the credit derivative transaction.
As a result, our maximum future payment is equal to the notional amount of the credit derivative.
In certain cases, we also have purchased credit protection with identical underlyings to certain of our sold protection transactions.
The effect of this purchased protection would reduce our total maximum future payments by $10.0 million and $47.0 million as of December 31, 2010 and 2009, respectively.
These credit derivative transactions had a net asset (liability) fair value of $(0.8) million and $2.4 million as of December 31, 2010 and 2009, respectively.
Our potential loss could also be reduced by any amount recovered in the default proceedings of the underlying credit name.
We purchased certain investment structures with embedded credit features that are fully consolidated into our financial statements.
This consolidation results in recognition of the underlying credit derivatives and collateral within the structure, typically high quality fixed maturities that are owned by a special purpose vehicle.
These credit derivatives reference a single name or several names in a basket structure.
In the event of default, the collateral within the structure would typically be liquidated to pay the claims of the credit derivative counterparty
Principal Financial Group, Inc.  Notes to Consolidated Financial Statements — (continued) 9.
Debt Short-Term Debt The components of short-term debt were as follows:
## Table 1 ##
As of December 31, 2010 and 2009, we had credit facilities with various financial institutions in an aggregate amount of $719.8 million and $681.9 million, respectively.
As of December 31, 2010 and 2009, we had $107.9 million and $101.6 million, respectively, of outstanding borrowings related to our credit facilities, with $28.4 million of assets pledged as support as of December 31, 2010.
As of both December 31, 2010 and 2009, our credit facilities included a $579.0 million commercial paper program, of which $50.0 million and $75.0 million was outstanding as of December 31, 2010 and 2009, respectively.
Our commercial paper program has a back-stop facility to provide 100% support for our commercial paper program, of which there were no outstanding balances as of December 31, 2010 and 2009.
The weighted-average interest rates on short-term borrowings as of December 31, 2010 and 2009, were 1.5% and 0.7%, respectively.
Long-Term Debt The components of long-term debt were as follows:
## Table 2 ##
The amounts included above are net of the discount and premium associated with issuing these notes, which are being amortized to expense over their respective terms using the interest method.
On November 3, 2010, Principal International de Chile S. A. , a wholly owned indirect subsidiary, entered into a long-term borrowing agreement with Banco de Chile in the amount of US $98.9 million.
This debt is denominated in Unidades de Formento (‘‘UF’’), a Chilean inflation-indexed, peso-denominated monetary unit.
The note bears interest at UF +3.76% and will mature on November 3, 2015.
Interest on the note is payable semi-annually on May 3 and November 3 each year.
This borrowing agreement consolidated and modified the terms of US $93.9 million of notes with two Chilean banks that were scheduled to mature on November 3, 2011.
The debt outstanding and interest expense will vary due to fluctuations in the Chilean peso to US dollar exchange rates and Chilean inflation.
On May 18, 2009, we issued $750.0 million of senior notes.
We issued a $400.0 million series of notes that bear interest at 7.875% and will mature on May 15, 2014, and a $350.0 million series of notes that bear interest at 8.875% and will mature on May 15, 2019.
Interest on the notes is payable semi-annually on May 15 and November 15 each year, beginning on November 15, 2009.
The proceeds were primarily used to refinance $440.9 million of notes that matured on August 15, 2009, with the remaining proceeds being used for general corporate purposes.
On October 16 and December 5, 2006, we issued $500.0 million and $100.0 million, respectively, of senior notes.
The notes bear interest at a rate of 6.05% per year.
Interest on the notes is payable semi-annually on April 15 and October 15 each year and began on April 15, 2007.
The notes will mature on October 15, 2036.
A portion of the proceeds were used to fund the 2006 acquisition of WM Advisors, Inc. , with the remaining proceeds being used for general corporate purposes.
On March 10, 1994, Principal Life issued $100.0 million of surplus notes due March 1, 2044, at an 8% annual interest rate.
None of our affiliates hold any portion of the notes.
Each payment of interest and principal on the notes, however,
The Railroad collected approximately $18.8 billion and $16.3 billion of receivables during the years ended December 31, 2011 and 2010, respectively.
UPRI used certain of these proceeds to purchase new receivables under the facility.
The costs of the receivables securitization facility include interest, which will vary based on prevailing commercial paper rates, program fees paid to banks, commercial paper issuing costs, and fees for unused commitment availability.
The costs of the receivables securitization facility are included in interest expense and were $4 million and $6 million for 2011 and 2010, respectively.
Prior to adoption of the new accounting standard, the costs of the receivables securitization facility were included in other income and were $9 million for 2009.
The investors have no recourse to the Railroad’s other assets, except for customary warranty and indemnity claims.
Creditors of the Railroad do not have recourse to the assets of UPRI.
In August 2011, the receivables securitization facility was renewed for an additional 364-day period at comparable terms and conditions.
Contractual Obligations and Commercial Commitments As described in the notes to the Consolidated Financial Statements and as referenced in the tables below, we have contractual obligations and commercial commitments that may affect our financial condition.
Based on our assessment of the underlying provisions and circumstances of our contractual obligations and commercial commitments, including material sources of off-balance sheet and structured finance arrangements, other than the risks that we and other similarly situated companies face with respect to the condition of the capital markets (as described in Item 1A of Part II of this report), there is no known trend, demand, commitment, event, or uncertainty that is reasonably likely to occur that would have a material adverse effect on our consolidated results of operations, financial condition, or liquidity.
In addition, our commercial obligations, financings, and commitments are customary transactions that are similar to those of other comparable corporations, particularly within the transportation industry.
The following tables identify material obligations and commitments as of December 31, 2011:
## Table 3 ##
[a] Excludes capital lease obligations of $1,874 million and unamortized discount of $364 million.
Includes an interest component of $5,120 million.
[b] Includes leases for locomotives, freight cars, other equipment, and real estate.
[c] Represents total obligations, including interest component of $685 million.
[d] Purchase obligations include locomotive maintenance contracts; purchase commitments for fuel purchases, locomotives, ties, ballast, and rail; and agreements to purchase other goods and services.
For amounts where we cannot reasonably estimate the year of settlement, they are reflected in the Other column.
[e] Includes estimated other post retirement, medical, and life insurance payments and payments made under the unfunded pension plan for the next ten years.
No amounts are included for funded pension obligations as no contributions are currently required.
[f] Future cash flows for income tax contingencies reflect the recorded liability for unrecognized tax benefits, including interest and penalties, as of December 31, 2011.
Where we can reasonably estimate the years in which these liabilities may be settled, this is shown in the table.
For amounts where we cannot reasonably estimate the year of settlement, they are reflected in the Other column.

Tables referenced above, in order (Table 0 first):
<table><tr><td> </td><td colspan="2"> Derivative assets -1</td><td colspan="2"> Derivative liabilities -2</td></tr><tr><td> </td><td> December 31, 2010</td><td> December 31, 2009</td><td> December 31, 2010</td><td> December 31, 2009</td></tr><tr><td> </td><td colspan="4"><i>(in millions)</i> </td></tr><tr><td> Derivatives designated as hedging instruments</td><td></td><td></td><td></td><td></td></tr><tr><td>Interest rate contracts</td><td>$66.6</td><td>$81.5</td><td>$405.4</td><td>$309.1</td></tr><tr><td>Foreign exchange contracts</td><td>390.8</td><td>444.4</td><td>142.5</td><td>240.6</td></tr><tr><td>Total derivatives designated as hedging instruments</td><td>$457.4</td><td>$525.9</td><td>$547.9</td><td>$549.7</td></tr><tr><td> Derivatives not designated as hedging instruments</td><td></td><td></td><td></td><td></td></tr><tr><td>Interest rate contracts</td><td>$488.4</td><td>$433.5</td><td>$459.5</td><td>$336.8</td></tr><tr><td>Foreign exchange contracts</td><td>65.8</td><td>107.5</td><td>60.4</td><td>75.0</td></tr><tr><td>Equity contracts</td><td>64.9</td><td>149.8</td><td>31.7</td><td>—</td></tr><tr><td>Credit contracts</td><td>6.7</td><td>15.5</td><td>171.7</td><td>84.0</td></tr><tr><td>Other contracts</td><td>—</td><td>—</td><td>145.7</td><td>128.1</td></tr><tr><td>Total derivatives not designated as hedging instruments</td><td>$625.8</td><td>$706.3</td><td>$869.0</td><td>$623.9</td></tr><tr><td>Total derivative instruments</td><td>$1,083.2</td><td>$1,232.2</td><td>$1,416.9</td><td>$1,173.6</td></tr></table>
<table><tr><td> </td><td colspan="2"> December 31,</td></tr><tr><td> </td><td> 2010</td><td> 2009</td></tr><tr><td> </td><td colspan="2"><i>(in millions)</i> </td></tr><tr><td>Commercial paper</td><td>$50.0</td><td>$75.0</td></tr><tr><td>Other recourse short-term debt</td><td>57.9</td><td>26.6</td></tr><tr><td>Total short-term debt</td><td>$107.9</td><td>$101.6</td></tr></table>
<table><tr><td> </td><td colspan="2"> December 31,</td></tr><tr><td> </td><td> 2010</td><td> 2009</td></tr><tr><td> </td><td colspan="2"><i>(in millions)</i> </td></tr><tr><td>3.31% notes payable, due 2011</td><td>$—</td><td>$61.2</td></tr><tr><td>3.63% notes payable, due 2011</td><td>—</td><td>31.4</td></tr><tr><td>7.875% notes payable, due 2014</td><td>400.0</td><td>400.0</td></tr><tr><td>3.76% notes payable, due 2015</td><td>102.8</td><td>—</td></tr><tr><td>8.875% notes payable, due 2019</td><td>350.0</td><td>350.0</td></tr><tr><td>6.05% notes payable, due 2036</td><td>601.7</td><td>601.8</td></tr><tr><td>8% surplus notes payable, due 2044</td><td>99.3</td><td>99.2</td></tr><tr><td>Non-recourse mortgages and notes payable</td><td>29.5</td><td>40.6</td></tr><tr><td>Other mortgages and notes payable</td><td>0.4</td><td>0.4</td></tr><tr><td>Total long-term debt</td><td>$1,583.7</td><td>$1,584.6</td></tr></table>
<table><tr><td></td><td></td><td colspan="7"><i>Payments Due by December 31,</i></td></tr><tr><td> <i>Contractual Obligations</i><i>Millions</i></td><td><i>Total</i></td><td><i>2012</i></td><td><i>2013</i></td><td><i>2014</i></td><td><i>2015</i></td><td><i>2016</i></td><td><i>After 2016</i></td><td><i>Other</i></td></tr><tr><td>Debt [a]</td><td>$12,516</td><td>$538</td><td>$852</td><td>$887</td><td>$615</td><td>$652</td><td>$8,972</td><td>$-</td></tr><tr><td>Operating leases [b]</td><td>4,528</td><td>525</td><td>489</td><td>415</td><td>372</td><td>347</td><td>2,380</td><td>-</td></tr><tr><td>Capital lease obligations [c]</td><td>2,559</td><td>297</td><td>269</td><td>276</td><td>276</td><td>262</td><td>1,179</td><td>-</td></tr><tr><td>Purchase obligations [d]</td><td>5,137</td><td>2,598</td><td>568</td><td>560</td><td>276</td><td>245</td><td>858</td><td>32</td></tr><tr><td>Other post retirement benefits [e]</td><td>249</td><td>26</td><td>26</td><td>26</td><td>26</td><td>26</td><td>119</td><td>-</td></tr><tr><td>Income tax contingencies [f]</td><td>107</td><td>31</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td><td>76</td></tr><tr><td>Total contractualobligations</td><td>$25,096</td><td>$4,015</td><td>$2,204</td><td>$2,164</td><td>$1,565</td><td>$1,532</td><td>$13,508</td><td>$108</td></tr></table>

Question: What is the growing rate of Interest rate contracts in the years with the least Interest rate contracts?
Answer: 0.23056
Reasoning program: add(488.4,459.5), add(433.5,336.8), subtract(#0,#1), add(433.5,336.8), divide(#2,#3)