(Wells Fargo Cost of Savings Index)






COSI Definition

What is the Wells Fargo Cost of Savings Index?

The Cost of Savings Index is based upon the interest rates paid by Wells Fargo’s banks on certificates of deposits held by individual depositors as of the last business day of each month.  This index is specific to the Wells Fargo banking group and is a weighted average of the relevant deposits.  The COSI is basically reflective of the rate Wells Fargo is currently paying to individuals for their CD’s, also known as personal time deposits.  Our reporting of this rate is based upon availability of data from Wells Fargo and usually lags about 1 month. (Rates reported starting November 2009 are Wells Fargo COSI, from July 2007 to October 2009 are Wachovia COSI, and prior to July 2007 are World Savings COSI.)

History:  December 14, 2009:  The Wells Fargo COSI replaced the Wachovia COSI effective with their publication of the November 2009 COSI Rate.  June 2009:  Wells Fargo/Wachovia has resumed publication of the COSI rate.  March 2009:  Wachovia has again discontinued providing this rate to the public on its website.  Since Wachovia was purchased by Wells Fargo there has been no indication of a substitute index.  There is speculation that the COSI has not moved down because it only reflects high-rate CD’s on the books of the old Wachovia entity.  See our blog on this topic:   February 2009:  Wachovia has resumed providing this rate to the public on its website.  December 2008:  Wachovia has discontinued providing this rate to the public.  See our blog on this topic:   The bank will continue to provide its COSI loan customers with updated rates on their monthly statements.  If you are a customer and want to share your rate information, feel free to make comments on our blog through the link above.]  June 2007:   The World Savings COSI was discontinued in June 2007 and replaced by the Wachovia Cost of Savings Index.  Rates published prior to July 2007 are the World Savings/Golden West COSI.  Rates thereafter reflect the new Wachovia COSI.


COSI - Graph - Cost of Saving Index


COSI History

COSI - Chart - Cost of Savings Index


Source: Wells Fargo, Wachovia, World Savings


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