We calculate the aging of customer accounts based on the monthly billing cycle for each account. On that basis, at December 31, 2015, September 30, 2015 and December 31, 2014, customers include approximately 38,100, 36,800 and 35,100 customers, respectively, whose accounts were over 60 days, approximately 1,700, 1,200 and 1,500 customers, respectively, whose accounts were over 90 days and approximately 900, 800 and 900 customers, respectively, whose accounts were over 120 days.
Passings represent our estimate of the number of units, such as single family homes, apartment and condominium units and small and medium business and enterprise sites passed by our cable distribution network in the areas where we offer the service indicated. These estimates are based upon the information available at this time and are updated for all periods presented when new information becomes available.
Penetration represents residential and small and medium business customers as a percentage of estimated passings for the service indicated.
Customer relationships include the number of customers that receive one or more levels of service, encompassing video, Internet and voice services, without regard to which service(s) such customers receive. Total customer relationships excludes enterprise customer relationships.
Charter revised its methodology for counting customers who reside in residential multiple dwelling units ("MDUs") that are billed under bulk contracts. Beginning in the fourth quarter of 2015, we count and report customers based on the number of billed units within each bulk MDU, similar to recent reporting changes at our peers and reflecting the completion of all-digital which requires a direct billing relationship for all units which receive a set-top box. Previously, our methodology for reporting residential customers generally excluded units under bulk arrangements, unless those units had a direct billing relationship. Prior year information has been revised to reflect our revised methodology.
Single play, double play and triple play customers represent customers that subscribe to one, two or three of Charter service offerings, respectively.
Single play, double play and triple play penetration represents the number of residential single play, double play and triple play customers, respectively, as a percentage of residential customer relationships.
Monthly residential revenue per residential customer is calculated as total residential video, Internet and voice quarterly revenue divided by three divided by average residential customer relationships during the respective quarter.
Charter revised its methodology for counting small and medium business video customers. Beginning in the fourth quarter of 2015, small and medium business customers are counted based on the number of customer locations. Previously, we had counted and reported video customers on an equivalent bulk unit (“EBU”) basis. EBUs were calculated by dividing the bulk price charged to accounts in an area by the published rate charged to non-bulk residential customers in that market for the comparable tier of service. Prior year information has been revised to reflect our revised methodology.
Monthly small and medium business revenue per customer is calculated as total small and medium business quarterly revenue divided by three divided by average small and medium business customer relationships during the respective quarter.
Enterprise PSUs represents the aggregate number of Charter's fiber service offerings counting each separate service offering at each customer location as an individual PSU.
Addendum to Charter Communications, Inc. Fourth Quarter 2015 Earnings Release
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