to date , a substantial majority of our revenue has come from sales of subscriptions of castlight medical . we believe that there is a significant opportunity to sell subscriptions to other applications as our customers become more familiar with our offering and seek to address additional needs . annual net dollar retention rate and average annual revenue . we believe that our ability to retain our customers and expand their subscription revenue growth over time will be an indicator of the stability of our revenue base and the long-term value of our customer relationships . because we typically enter into long-term contracts with our customers , only a small percentage of our customer agreements have reached the end of their original terms and , as a result , we have not observed a large enough sample of renewals to derive meaningful conclusions . based on our limited experience , we observed an annual net dollar retention rate of 103 % for our signed customer base , for the year ended december 31 , 2014 . additionally , our average annual revenue per launched customer grew approximately 17 % for the year ended december 31 , 2014 compared to the year ended december 31 , 2013 . we calculate annual net dollar retention rate for a given period as the aggregate annualized subscription contract value as of the last day of that year from those customers that were also customers as of the last day of the prior year , divided by the aggregate annualized subscription contract value from all customers as of the last day of the prior year . we calculate annualized subscription contract value for each customer as the expected monthly recurring revenue of our customers multiplied by 12. recurring revenue excludes one-time fees . we calculate average annual revenue per launched customer for a given period , as the annualized revenue as of the last day of the year , divided by average customers launched during the same period . implementation timelines . our ability to convert backlog into revenue and improve our gross margin depends on how quickly we complete customer implementations . our implementation timelines vary from customer to customer based on the source and condition of the data we receive from third parties , the configurations that we agree to provide and the size of the customer . our implementation timelines for castlight medical are typically three to nine months after entering into an agreement with a customer . our implementation timelines for our other applications typically range from approximately six months to longer than twelve months . 35 professional services model . we believe our professional services capabilities support the adoption of our subscription offerings . as a result , our sales efforts have been focused primarily on our subscription offering , rather than the profitability of our professional services business . our professional services are generally priced on a fixed-fee basis and the costs incurred to complete these services , which consist mainly of personnel-related costs , have been greater than the amount charged to the customer . we also do not have standalone value for our implementation services for accounting purposes . accordingly , we recognize implementation services revenue in the same manner as the associated subscription revenue . prior to launching an individual customer , we incur significant costs associated with implementation activities , which we record as cost of revenue . since we do not recognize significant revenues from an individual customer until we launch , we generate a negative gross margin at the customer level during the implementation period . seasonality . a significantly higher proportion of our customers enter into new subscription agreements with us or renew previous agreements in the third and fourth quarters of the year compared to the first and second quarters . this seasonality is related to the employee benefits cycle , as customers typically want to make our applications available at the beginning of a new benefits year , which generally occurs in the first quarter . this seasonality is not immediately apparent in our revenue because we do not begin recognizing revenue from new customer agreements until we have implemented our offering , based on the implementation timelines discussed above . therefore , revenue recognized in any quarter is primarily from customer agreements entered into in prior quarters . in addition , the mix of customers paying monthly , quarterly , or annually varies from quarter to quarter and impacts our deferred revenue balance . as a result of variability in our billing and implementation timelines , the deferred revenue balance does not represent the total value of our customer contracts , nor do changes in deferred revenue serve as a reliable indicator of our future subscription revenue . components of results of operations revenue we generate revenue from subscription fees from customers for access to selected applications in the castlight enterprise healthcare cloud including basic customer service support . we also earn revenue from professional services primarily related to the implementation of our offering , including extensive communications support to drive adoption by our customers ' employees and their families . we recognize subscription fees on a straight-line basis ratably over the contract term beginning when our applications are implemented and ready for launch , which is based on the implementation timelines discussed above . our customer agreements generally have a term of three years . we generally invoice our customers in advance on a monthly , quarterly or annual basis . amounts that have been invoiced are initially recorded as deferred revenue . amounts that have not been invoiced are not reflected in our consolidated financial statements . we generally invoice our implementation services upon contract signing on a fixed-fee basis , which is generally when we commence work . story_separator_special_tag revenue is recognized based on the terms in our customer contracts , which can provide for ( a ) a variable periodic fee based upon the actual or contractual number of users that is recognized to revenue based on the actual or contractual number of users or ( b ) a fixed fee that is recognized to revenue on a straight-line basis over the contractual term of the arrangement . certain of our cloud-based subscription arrangements include performance incentives that are generally based upon employee engagement . fees for performance incentives are considered contingent revenue , and are recognized over the remaining term of the related subscription arrangement commencing at the time they are earned . professional services revenue . professional services revenue is comprised of implementation services related to our cloud-based subscription service , as well as follow-on professional services to assist our customers in further adopting our cloud-based subscription service , and communications services . nearly all of our professional services contracts are sold on a fixed-fee basis . we do not have standalone value for our implementation services . accordingly , we recognize implementation services revenue in the same manner as the associated cloud-based subscription service , beginning on the launch date , provided all other criteria described above have been met . for follow-on professional services that are sold separately from the cloud-based subscription service , we recognize revenue as the services are delivered . communication services revenue is recognized over the contractual term , generally one year , commencing when the revenue recognition criteria have been met . 43 multiple deliverable arrangements . to date , we have generated substantially all our revenue from multiple deliverable arrangements consisting of multi-year cloud-based subscription services and professional services , including implementation services and communication services . for arrangements with multiple deliverables , we evaluate whether the individual deliverables qualify as separate units of accounting . in order to treat deliverables in a multiple deliverable arrangement as separate units of accounting , the deliverables must have standalone value upon delivery . if the deliverables have standalone value upon delivery , we account for each deliverable separately and revenue is recognized for the respective deliverables as they are delivered . if one or more of the deliverables do not have standalone value upon delivery , the deliverables that do not have standalone value are generally combined with our cloud-based subscription service , and revenue for the combined unit is recognized over the remaining term of the cloud-based subscription service . our deliverables have standalone value if we or any other vendor sells a similar service separately . we have concluded that we have standalone value for our cloud-based subscription service as we sell these services separately through renewals and for our communication services as other vendors sell similar services separately . conversely , we have concluded that our implementation services do not have standalone value , as we and others do not yet sell these services separately . accordingly , we consider the separate units of accounting in our multiple deliverable arrangements to be the communication services and a combined deliverable comprised of cloud-based subscription services and implementation services . when multiple deliverables included in an arrangement are separable into different units of accounting , the arrangement consideration is allocated to the identified separate units of accounting based on their relative selling price . multiple deliverable arrangements accounting guidance provides a hierarchy to use when determining the relative selling price for each unit of accounting . vendor-specific objective evidence , or vsoe , of selling price , based on the price at which the item is regularly sold by the vendor on a standalone basis , should be used if it exists . if vsoe of selling price is not available , third-party evidence , or tpe , of selling price is used to establish the selling price if it exists . if tpe does not exist , we estimate the best estimated selling price , or besp . vsoe does not currently exist for any of our deliverables . additionally , we do not believe tpe is a practical alternative due to differences in our cloud-based subscription service compared to other parties and the availability of relevant third-party pricing information for our cloud-based subscription service and our other services . accordingly , for arrangements with multiple deliverables that can be separated into different units of accounting , we allocate the arrangement fee to the separate units of accounting based on our besp . the amount of arrangement fee allocated is limited by contingent revenue , if any . we determine besp for our deliverables by considering our overall pricing objectives and market conditions . this includes evaluating our pricing practices , our list prices , the size of our transactions , historical sales and our go-to-market strategy . the determination of besp is made through consultation with and approval by management . for financial statement presentation purposes , we allocate the fees from our combined units of accounting to subscription and professional services based upon their relative selling price . deferred commissions deferred commissions are the incremental costs that are directly associated with the non-cancellable portion of cloud-based subscription service contracts with customers and consist of sales commissions paid to our direct sales force . the commissions are deferred and amortized over the non-cancellable terms of the related contracts . the deferred commission amounts are recoverable through the future revenue streams under the non-cancellable customer contracts . amortization of deferred commissions is included in sales and marketing expense in the consolidated statements of operations . stock-based compensation compensation expense related to stock-based transactions , including employee , consultant and non-employee director stock option awards , is measured and recognized in the financial statements based on fair value . the fair value of each option award is estimated on the grant date using the black-scholes option-pricing model . the stock-based compensation expense , net of forfeitures , is recognized

liquidity and capital resources replace_table_token_11_th 40 as of december 31 , 2014 , our principal sources of liquidity were cash , cash equivalents and marketable securities totaling $ 198.7 million , which were held for working capital purposes . our cash , cash equivalents and marketable securities are comprised primarily of u.s. agency obligations , u.s. treasury securities and money market funds . since our inception , we have financed our operations primarily through sales of equity securities and to a lesser extent , payments from our customers . we believe that our existing cash , cash equivalents and marketable securities will be sufficient to meet our working capital and capital expenditure needs for at least the next 12 months . our future capital requirements will depend on many factors including our growth rate , subscription renewal activity , the timing and extent of spending to support development efforts , our expansion of sales and marketing activities , the introduction of new and enhanced services offerings and the continuing market acceptance of our cloud-based applications . we may in the future enter into arrangements to acquire or invest in complementary businesses , services and technologies and intellectual property rights . we may be required to seek additional equity or debt financing . in the event that additional financing is required from outside sources , we may not be able to raise it on terms acceptable to us or at all . if we are unable to raise additional capital when desired , our business , operating results and financial condition would be adversely affected . operating activities for the year ended december 31 , 2014 , cash used in operating activities was $ 54.6 million .


 Write a concise suspicious activity report of the following text delimited by triple backquotes. Return your response as a formal report which covers the key points highlighting the location,dates,entity names and account holder information in chronological order of the text.
     ```liquidity and capital resources replace_table_token_11_th 40 as of december 31 , 2014 , our principal sources of liquidity were cash , cash equivalents and marketable securities totaling $ 198.7 million , which were held for working capital purposes . our cash , cash equivalents and marketable securities are comprised primarily of u.s. agency obligations , u.s. treasury securities and money market funds . since our inception , we have financed our operations primarily through sales of equity securities and to a lesser extent , payments from our customers . we believe that our existing cash , cash equivalents and marketable securities will be sufficient to meet our working capital and capital expenditure needs for at least the next 12 months . our future capital requirements will depend on many factors including our growth rate , subscription renewal activity , the timing and extent of spending to support development efforts , our expansion of sales and marketing activities , the introduction of new and enhanced services offerings and the continuing market acceptance of our cloud-based applications . we may in the future enter into arrangements to acquire or invest in complementary businesses , services and technologies and intellectual property rights . we may be required to seek additional equity or debt financing . in the event that additional financing is required from outside sources , we may not be able to raise it on terms acceptable to us or at all . if we are unable to raise additional capital when desired , our business , operating results and financial condition would be adversely affected . operating activities for the year ended december 31 , 2014 , cash used in operating activities was $ 54.6 million .
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 Suspicious Activity Report : to date , a substantial majority of our revenue has come from sales of subscriptions of castlight medical . we believe that there is a significant opportunity to sell subscriptions to other applications as our customers become more familiar with our offering and seek to address additional needs . annual net dollar retention rate and average annual revenue . we believe that our ability to retain our customers and expand their subscription revenue growth over time will be an indicator of the stability of our revenue base and the long-term value of our customer relationships . because we typically enter into long-term contracts with our customers , only a small percentage of our customer agreements have reached the end of their original terms and , as a result , we have not observed a large enough sample of renewals to derive meaningful conclusions . based on our limited experience , we observed an annual net dollar retention rate of 103 % for our signed customer base , for the year ended december 31 , 2014 . additionally , our average annual revenue per launched customer grew approximately 17 % for the year ended december 31 , 2014 compared to the year ended december 31 , 2013 . we calculate annual net dollar retention rate for a given period as the aggregate annualized subscription contract value as of the last day of that year from those customers that were also customers as of the last day of the prior year , divided by the aggregate annualized subscription contract value from all customers as of the last day of the prior year . we calculate annualized subscription contract value for each customer as the expected monthly recurring revenue of our customers multiplied by 12. recurring revenue excludes one-time fees . we calculate average annual revenue per launched customer for a given period , as the annualized revenue as of the last day of the year , divided by average customers launched during the same period . implementation timelines . our ability to convert backlog into revenue and improve our gross margin depends on how quickly we complete customer implementations . our implementation timelines vary from customer to customer based on the source and condition of the data we receive from third parties , the configurations that we agree to provide and the size of the customer . our implementation timelines for castlight medical are typically three to nine months after entering into an agreement with a customer . our implementation timelines for our other applications typically range from approximately six months to longer than twelve months . 35 professional services model . we believe our professional services capabilities support the adoption of our subscription offerings . as a result , our sales efforts have been focused primarily on our subscription offering , rather than the profitability of our professional services business . our professional services are generally priced on a fixed-fee basis and the costs incurred to complete these services , which consist mainly of personnel-related costs , have been greater than the amount charged to the customer . we also do not have standalone value for our implementation services for accounting purposes . accordingly , we recognize implementation services revenue in the same manner as the associated subscription revenue . prior to launching an individual customer , we incur significant costs associated with implementation activities , which we record as cost of revenue . since we do not recognize significant revenues from an individual customer until we launch , we generate a negative gross margin at the customer level during the implementation period . seasonality . a significantly higher proportion of our customers enter into new subscription agreements with us or renew previous agreements in the third and fourth quarters of the year compared to the first and second quarters . this seasonality is related to the employee benefits cycle , as customers typically want to make our applications available at the beginning of a new benefits year , which generally occurs in the first quarter . this seasonality is not immediately apparent in our revenue because we do not begin recognizing revenue from new customer agreements until we have implemented our offering , based on the implementation timelines discussed above . therefore , revenue recognized in any quarter is primarily from customer agreements entered into in prior quarters . in addition , the mix of customers paying monthly , quarterly , or annually varies from quarter to quarter and impacts our deferred revenue balance . as a result of variability in our billing and implementation timelines , the deferred revenue balance does not represent the total value of our customer contracts , nor do changes in deferred revenue serve as a reliable indicator of our future subscription revenue . components of results of operations revenue we generate revenue from subscription fees from customers for access to selected applications in the castlight enterprise healthcare cloud including basic customer service support . we also earn revenue from professional services primarily related to the implementation of our offering , including extensive communications support to drive adoption by our customers ' employees and their families . we recognize subscription fees on a straight-line basis ratably over the contract term beginning when our applications are implemented and ready for launch , which is based on the implementation timelines discussed above . our customer agreements generally have a term of three years . we generally invoice our customers in advance on a monthly , quarterly or annual basis . amounts that have been invoiced are initially recorded as deferred revenue . amounts that have not been invoiced are not reflected in our consolidated financial statements . we generally invoice our implementation services upon contract signing on a fixed-fee basis , which is generally when we commence work . story_separator_special_tag revenue is recognized based on the terms in our customer contracts , which can provide for ( a ) a variable periodic fee based upon the actual or contractual number of users that is recognized to revenue based on the actual or contractual number of users or ( b ) a fixed fee that is recognized to revenue on a straight-line basis over the contractual term of the arrangement . certain of our cloud-based subscription arrangements include performance incentives that are generally based upon employee engagement . fees for performance incentives are considered contingent revenue , and are recognized over the remaining term of the related subscription arrangement commencing at the time they are earned . professional services revenue . professional services revenue is comprised of implementation services related to our cloud-based subscription service , as well as follow-on professional services to assist our customers in further adopting our cloud-based subscription service , and communications services . nearly all of our professional services contracts are sold on a fixed-fee basis . we do not have standalone value for our implementation services . accordingly , we recognize implementation services revenue in the same manner as the associated cloud-based subscription service , beginning on the launch date , provided all other criteria described above have been met . for follow-on professional services that are sold separately from the cloud-based subscription service , we recognize revenue as the services are delivered . communication services revenue is recognized over the contractual term , generally one year , commencing when the revenue recognition criteria have been met . 43 multiple deliverable arrangements . to date , we have generated substantially all our revenue from multiple deliverable arrangements consisting of multi-year cloud-based subscription services and professional services , including implementation services and communication services . for arrangements with multiple deliverables , we evaluate whether the individual deliverables qualify as separate units of accounting . in order to treat deliverables in a multiple deliverable arrangement as separate units of accounting , the deliverables must have standalone value upon delivery . if the deliverables have standalone value upon delivery , we account for each deliverable separately and revenue is recognized for the respective deliverables as they are delivered . if one or more of the deliverables do not have standalone value upon delivery , the deliverables that do not have standalone value are generally combined with our cloud-based subscription service , and revenue for the combined unit is recognized over the remaining term of the cloud-based subscription service . our deliverables have standalone value if we or any other vendor sells a similar service separately . we have concluded that we have standalone value for our cloud-based subscription service as we sell these services separately through renewals and for our communication services as other vendors sell similar services separately . conversely , we have concluded that our implementation services do not have standalone value , as we and others do not yet sell these services separately . accordingly , we consider the separate units of accounting in our multiple deliverable arrangements to be the communication services and a combined deliverable comprised of cloud-based subscription services and implementation services . when multiple deliverables included in an arrangement are separable into different units of accounting , the arrangement consideration is allocated to the identified separate units of accounting based on their relative selling price . multiple deliverable arrangements accounting guidance provides a hierarchy to use when determining the relative selling price for each unit of accounting . vendor-specific objective evidence , or vsoe , of selling price , based on the price at which the item is regularly sold by the vendor on a standalone basis , should be used if it exists . if vsoe of selling price is not available , third-party evidence , or tpe , of selling price is used to establish the selling price if it exists . if tpe does not exist , we estimate the best estimated selling price , or besp . vsoe does not currently exist for any of our deliverables . additionally , we do not believe tpe is a practical alternative due to differences in our cloud-based subscription service compared to other parties and the availability of relevant third-party pricing information for our cloud-based subscription service and our other services . accordingly , for arrangements with multiple deliverables that can be separated into different units of accounting , we allocate the arrangement fee to the separate units of accounting based on our besp . the amount of arrangement fee allocated is limited by contingent revenue , if any . we determine besp for our deliverables by considering our overall pricing objectives and market conditions . this includes evaluating our pricing practices , our list prices , the size of our transactions , historical sales and our go-to-market strategy . the determination of besp is made through consultation with and approval by management . for financial statement presentation purposes , we allocate the fees from our combined units of accounting to subscription and professional services based upon their relative selling price . deferred commissions deferred commissions are the incremental costs that are directly associated with the non-cancellable portion of cloud-based subscription service contracts with customers and consist of sales commissions paid to our direct sales force . the commissions are deferred and amortized over the non-cancellable terms of the related contracts . the deferred commission amounts are recoverable through the future revenue streams under the non-cancellable customer contracts . amortization of deferred commissions is included in sales and marketing expense in the consolidated statements of operations . stock-based compensation compensation expense related to stock-based transactions , including employee , consultant and non-employee director stock option awards , is measured and recognized in the financial statements based on fair value . the fair value of each option award is estimated on the grant date using the black-scholes option-pricing model . the stock-based compensation expense , net of forfeitures , is recognized

