amount of commitment expiration per period other commercial commitments after millions total 2013 2014 2015 2016 2017 2017 .

Table:
other commercial commitmentsmillions | total | amount of commitment expiration per period 2013 | amount of commitment expiration per period 2014 | amount of commitment expiration per period 2015 | amount of commitment expiration per period 2016 | amount of commitment expiration per period 2017 | amount of commitment expiration per period after 2017
credit facilities [a] | $ 1800 | $ - | $ - | $ 1800 | $ - | $ - | $ -
receivables securitization facility [b] | 600 | 600 | - | - | - | - | -
guarantees [c] | 307 | 8 | 214 | 12 | 30 | 10 | 33
standby letters of credit [d] | 25 | 24 | 1 | - | - | - | -
total commercialcommitments | $ 2732 | $ 632 | $ 215 | $ 1812 | $ 30 | $ 10 | $ 33
[a] none of the credit facility was used as of december 31 , 2012 .
[b] $ 100 million of the receivables securitization facility was utilized at december 31 , 2012 , which is accounted for as debt .
the full program matures in july 2013 .
[c] includes guaranteed obligations related to our headquarters building , equipment financings , and affiliated operations .
[d] none of the letters of credit were drawn upon as of december 31 , 2012 .
off-balance sheet arrangements guarantees 2013 at december 31 , 2012 , we were contingently liable for $ 307 million in guarantees .
we have recorded a liability of $ 2 million for the fair value of these obligations as of december 31 , 2012 and 2011 .
we entered into these contingent guarantees in the normal course of business , and they include guaranteed obligations related to our headquarters building , equipment financings , and affiliated operations .
the final guarantee expires in 2022 .
we are not aware of any existing event of default that would require us to satisfy these guarantees .
we do not expect that these guarantees will have a material adverse effect on our consolidated financial condition , results of operations , or liquidity .
other matters labor agreements 2013 approximately 86% ( 86 % ) of our 45928 full-time-equivalent employees are represented by 14 major rail unions .
during the year , we concluded the most recent round of negotiations , which began in 2010 , with the ratification of new agreements by several unions that continued negotiating into 2012 .
all of the unions executed similar multi-year agreements that provide for higher employee cost sharing of employee health and welfare benefits and higher wages .
the current agreements will remain in effect until renegotiated under provisions of the railway labor act .
the next round of negotiations will begin in early 2015 .
inflation 2013 long periods of inflation significantly increase asset replacement costs for capital-intensive companies .
as a result , assuming that we replace all operating assets at current price levels , depreciation charges ( on an inflation-adjusted basis ) would be substantially greater than historically reported amounts .
derivative financial instruments 2013 we may use derivative financial instruments in limited instances to assist in managing our overall exposure to fluctuations in interest rates and fuel prices .
we are not a party to leveraged derivatives and , by policy , do not use derivative financial instruments for speculative purposes .
derivative financial instruments qualifying for hedge accounting must maintain a specified level of effectiveness between the hedging instrument and the item being hedged , both at inception and throughout the hedged period .
we formally document the nature and relationships between the hedging instruments and hedged items at inception , as well as our risk-management objectives , strategies for undertaking the various hedge transactions , and method of assessing hedge effectiveness .
changes in the fair market value of derivative financial instruments that do not qualify for hedge accounting are charged to earnings .
we may use swaps , collars , futures , and/or forward contracts to mitigate the risk of adverse movements in interest rates and fuel prices ; however , the use of these derivative financial instruments may limit future benefits from favorable price movements .
market and credit risk 2013 we address market risk related to derivative financial instruments by selecting instruments with value fluctuations that highly correlate with the underlying hedged item .
we manage credit risk related to derivative financial instruments , which is minimal , by requiring high credit standards for counterparties and periodic settlements .
at december 31 , 2012 and 2011 , we were not required to provide collateral , nor had we received collateral , relating to our hedging activities. .

Question: what percentage of total commercial commitments are credit facilities?
Answer: 66%
Calculation: divide(1800, 2732)