it also features an easy-to-navigate software architecture , a vivid color touch screen and a micro-usb connection that supports both a rechargeable battery and t : connect , our custom cloud-based data management application that provides a fast , easy and visual way to display therapy management data from the pump and supported blood glucose meters . we began commercial sales of our first product , t : slim , in august 2012. during 2015 , we commenced commercial sales of two additional insulin pumps : t : flex in may 2015 and t : slim g4 in september 2015. since inception , we have derived nearly all of our revenue from the sale of insulin pumps and associated supplies in the united states . we consider the number of units shipped per quarter to be an important metric for managing our business . we have shipped nearly 34,000 insulin pumps since the initiation of our commercial efforts in 2012. pump shipments are broken down by product , and by quarter as follows : 56 replace_table_token_4_th ( 1 ) this table does not reflect returns or exchanges of pump products that occurred in the ordinary course of business . ( 2 ) during the fourth quarter of 2015 , 148 t : slim pumps and two t : flex pumps originally shipped in the third quarter of 2015 were exchanged for t : slim g4 pumps under a limited product exchange program ( as described below ) . amounts for the fourth quarter of 2015 in the table above are adjusted to reflect the impact of the exchange program . for the years ended december 31 , 2015 , 2014 and 2013 , our sales were $ 72.9 million , $ 49.7 million and $ 29.0 million , respectively . for the years ended december 31 , 2015 , 2014 and 2013 , our net loss was $ 72.4 million , $ 79.5 million and $ 63.1 million , respectively . our accumulated deficit as of december 31 , 2015 was $ 321.1 million . in connection with t : slim g4 commercial launch , we offered a limited product exchange program , referred to as the exchange program for eligible customers . the exchange program offered customers who received a t : slim or t : flex pump on or after august 1 , 2015 , a limited period in which to elect to exchange their pump for a t : slim g4 . the ability to elect an exchange ended in the early part of october 2015. at the close of the exchange program , a total of 150 t : slim or t : flex pumps were exchanged for t : slim g4 pumps . we accrued for estimated exchanges and associated costs by reducing sales and deferring cost of sales in the third quarter of 2015. the deferred sales and the cost of sales under the exchange program were recognized either upon delivery of t : slim g4 to the customer during the fourth quarter of 2015 or expiration of the program for those that were not exchanged . in the fourth quarter , t : slim g4 made up majority of our overall shipments . while there is some cannibalization of t : slim , and this high percentage may also reflect some pent up demand , we also believe this trend demonstrates that there is significant interest in this product . we expect that t : slim g4 will represent the largest percentage of our pump shipments in 2016. a substantial portion of the purchase price of an insulin pump is typically paid for by third-party payors , including private insurance companies , preferred provider organizations and other managed care providers . access to adequate coverage and reimbursement for our current and future products by third-party payors is essential to the acceptance of our products by customers . future sales of our current and future products will be limited unless our customers can rely on third-party payors to pay for all or part of the associated purchase cost . in circumstances in which we do not have contracts established with third-party payors , to the extent possible , we utilize our network of national and regional distributors to service our customers . 57 we believe we can achieve profitability because our proprietary technology platform will allow us to maximize efficiencies in the development , production and sale of our products . by offering a family of products , all of which are based on our proprietary technology platform , we believe we can develop and bring to market products more rapidly , while significantly reducing our design and development costs . due to shared product design features , ou r production system is adaptable to new products and we intend to leverage our shared manufacturing infrastructure to reduce our product costs and drive operational efficiencies . further , we expect to continue to increase production volume and to reduce th e per-unit production overhead cost for our pump products and their associated disposable cartridges over time . by expanding our product offerings to address people in different segments of the large and growing insulin-dependent diabetes market , we believ e we can increase the productivity of our sales , clinical and marketing organization , and utilize the expertise of our customer , technical and support services , thereby improving our operating margin . from inception through december 31 , 2015 , we have primarily financed our operations through sales of equity securities , and to a lesser extent , debt financings . we expect to continue to incur net losses for the next several years , and may require additional capital through equity and debt financings in order to fund our operations until we reach a level of revenue adequate to support our cost structure . story_separator_special_tag sales from t : slim pump accounted for 86 % and 90 % of sales , respectively , for the years ended december 31 , 2014 and 2013 , while pump-related supplies primarily accounted for the remainder in each year . sales of accessories were not material in either year . the growth in sales was primarily driven by a 67 % increase in t : slim pump shipments from 6,472 in 2013 to 10,822 in 2014. we expanded the number of sales territories in the united states from 36 at the end of 2013 to 60 at the end of the second quarter of 2014. as a result of our sales force expansion , our field personnel experienced some initial disruption in their sales productivity as their territories were realigned and responsibilities adjusted . 61 sales to distributors accounted for 75 % and 69 % of our total sales for the years ended december 31 , 2014 and 2013 , respectively . the increase in the percentage of our sales to distributors is primarily attributable to certain arrangements between insurance payors and our distributors that becam e effective during the third quarter of 2014. as a result of these arrangements , a portion of our business that previously involved an opportunity to make a direct sale to the customer transitioned to an opportunity to make a sale through a distributor . th e new arrangement afforded certain members easier access to our products as an in-network benefit and provided access to our products to a large portion of members who were previously unable to obtain coverage for our products at all . cost of sales and gross profit . our cost of sales in 2014 was $ 34.5 million , resulting in gross profit of $ 15.2 million , compared to $ 22.8 million in cost of sales and gross profit of $ 6.2 million in 2013. the gross margin in 2014 was 31 % , compared to 21 % in 2013. the improvement in the gross margin was primarily a result of manufacturing efficiencies associated with an increase in production output and improvement in our manufacturing processes . our pump manufacturing overhead spending decreased 19 % while our pump units produced increased 56 % in 2014 compared to 2013 , and our cartridge manufacturing overhead spending increased 40 % while our cartridge units produced increased 143 % in 2014 compared to 2013. included in cost of sales for the year ended december 31 , 2014 were costs of $ 0.4 million associated with our voluntary product recall of selected lots of cartridges initiated in january 2014. the voluntary recall resulted in a less than one percentage point reduction in the gross margin for the year ended december 31 , 2014. by comparison , the 2013 gross margin included $ 1.3 million of recall-associated costs , or a reduction of the gross margin of five percentage points . also included in cost of sales in 2013 were costs of $ 1.1 million that were previously deferred at the end of the fourth quarter of 2012 due to our lack of history for estimating product returns at that time . these costs , along with the previously deferred sales of $ 1.9 million recognized in the first quarter of 2013 , resulted in a two-percentage point increase in gross margin for the year ended december 31 , 2013. selling , general and administrative expenses . sg & a expenses increased 69 % to $ 75.1 million in 2014 from $ 44.5 million in 2013. the increase in sg & a expenses was primarily associated with the expansion of our commercial operations during 2014. as of december 31 , 2014 , our headcount for sales , general and administrative functions increased 43 % compared to december 31 , 2013. this includes an expansion from 36 to 60 territories during 2014 , as well as the growth of the administrative infrastructure to support operations . territories are maintained by sales representatives , field clinical specialists , managed care liaisons , additional sales management and other customer support personnel . employee-related expenses for our sales , general and administrative functions comprise the majority of the sg & a expenses . such employee-related expenses increased $ 24.9 million during 2014 compared to 2013 , including an increase of $ 8.3 million in stock-based compensation associated with equity awards . sg & a expenses also increased $ 5.7 million associated with marketing and promotional activities , tradeshows , travel expenses and facility expansion . research and development expenses . r & d expenses increased 43 % to $ 15.8 million in 2014 from $ 11.1 million in 2013. the increase in r & d expenses in 2014 consisted primarily of an increase of $ 2.5 million in employee-related expenses . at december 31 , 2014 , our headcount for research and development functions increased 17 % compared to december 31 , 2013. the increase in r & d expenses also consisted of a milestone payment of $ 1.0 million to dexcom under our development and commercialization agreement related to our submission of a pma for t : slim g4 to the fda in july 2014. other income ( expense ) . other expense in 2014 was $ 3.8 million , compared to $ 13.7 million in 2013. other expense in 2014 primarily consisted of interest expense associated with the term loan agreement with capital royalty partners in december 2012 and subsequently amended and restated in april 2014 , and further amended in june 2014 , february 2015 and january 2016. we borrowed $ 30 million under the term loan agreement with capital royalty partners in january 2013. in comparison , other expense in 2013 was primarily comprised of $ 9.0 million of expense associated with the revaluation of the fair value of common and preferred stock warrants and $ 4.7 million of interest expense associated with our term loan agreement with capital royalty partners .

liquidity and capital resources at december 31 , 2015 , we had $ 73.1 million in cash and cash equivalents and short-term investments , which included $ 2.0 million of restricted cash . we borrowed $ 15.0 million in january 2016 , under the third amendment to our term loan agreement with capital royalty partners . the third amendment also provides us with a one-time option to borrow up to an additional $ 35.0 million in increments of $ 5.0 million on or before december 31 , 2016. we believe that our cash on hand , cash generated from operations , cash available under the third amendment to our term loan agreement with capital royalty partners , and proceeds from the exercise of options and warrants , as well as proceeds from employee contributions for the purchase of our common stock through our espp , will be sufficient to satisfy our liquidity requirements for at least the next 12 months . we expect that our sales performance and the resulting operating income or loss , as well as the status of each of our new product development programs , will significantly impact our cash management decisions . we have utilized , and may continue to utilize , debt arrangements with debt providers and financial institutions to finance our operations . factors such as interest rates , repayment terms and available cash will impact our decision to continue to utilize debt arrangements as a source of cash . in november 2013 , we completed an initial public offering of common stock that resulted in net proceeds of approximately $ 125.0 million , and in the first quarter of 2015 we completed a public offering of common stock that resulted in net proceeds of approximately $ 64.9 million . in the future , we may give consideration to additional public offerings of equity securities as a source of financing .


 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 at december 31 , 2015 , we had $ 73.1 million in cash and cash equivalents and short-term investments , which included $ 2.0 million of restricted cash . we borrowed $ 15.0 million in january 2016 , under the third amendment to our term loan agreement with capital royalty partners . the third amendment also provides us with a one-time option to borrow up to an additional $ 35.0 million in increments of $ 5.0 million on or before december 31 , 2016. we believe that our cash on hand , cash generated from operations , cash available under the third amendment to our term loan agreement with capital royalty partners , and proceeds from the exercise of options and warrants , as well as proceeds from employee contributions for the purchase of our common stock through our espp , will be sufficient to satisfy our liquidity requirements for at least the next 12 months . we expect that our sales performance and the resulting operating income or loss , as well as the status of each of our new product development programs , will significantly impact our cash management decisions . we have utilized , and may continue to utilize , debt arrangements with debt providers and financial institutions to finance our operations . factors such as interest rates , repayment terms and available cash will impact our decision to continue to utilize debt arrangements as a source of cash . in november 2013 , we completed an initial public offering of common stock that resulted in net proceeds of approximately $ 125.0 million , and in the first quarter of 2015 we completed a public offering of common stock that resulted in net proceeds of approximately $ 64.9 million . in the future , we may give consideration to additional public offerings of equity securities as a source of financing .
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 Suspicious Activity Report : it also features an easy-to-navigate software architecture , a vivid color touch screen and a micro-usb connection that supports both a rechargeable battery and t : connect , our custom cloud-based data management application that provides a fast , easy and visual way to display therapy management data from the pump and supported blood glucose meters . we began commercial sales of our first product , t : slim , in august 2012. during 2015 , we commenced commercial sales of two additional insulin pumps : t : flex in may 2015 and t : slim g4 in september 2015. since inception , we have derived nearly all of our revenue from the sale of insulin pumps and associated supplies in the united states . we consider the number of units shipped per quarter to be an important metric for managing our business . we have shipped nearly 34,000 insulin pumps since the initiation of our commercial efforts in 2012. pump shipments are broken down by product , and by quarter as follows : 56 replace_table_token_4_th ( 1 ) this table does not reflect returns or exchanges of pump products that occurred in the ordinary course of business . ( 2 ) during the fourth quarter of 2015 , 148 t : slim pumps and two t : flex pumps originally shipped in the third quarter of 2015 were exchanged for t : slim g4 pumps under a limited product exchange program ( as described below ) . amounts for the fourth quarter of 2015 in the table above are adjusted to reflect the impact of the exchange program . for the years ended december 31 , 2015 , 2014 and 2013 , our sales were $ 72.9 million , $ 49.7 million and $ 29.0 million , respectively . for the years ended december 31 , 2015 , 2014 and 2013 , our net loss was $ 72.4 million , $ 79.5 million and $ 63.1 million , respectively . our accumulated deficit as of december 31 , 2015 was $ 321.1 million . in connection with t : slim g4 commercial launch , we offered a limited product exchange program , referred to as the exchange program for eligible customers . the exchange program offered customers who received a t : slim or t : flex pump on or after august 1 , 2015 , a limited period in which to elect to exchange their pump for a t : slim g4 . the ability to elect an exchange ended in the early part of october 2015. at the close of the exchange program , a total of 150 t : slim or t : flex pumps were exchanged for t : slim g4 pumps . we accrued for estimated exchanges and associated costs by reducing sales and deferring cost of sales in the third quarter of 2015. the deferred sales and the cost of sales under the exchange program were recognized either upon delivery of t : slim g4 to the customer during the fourth quarter of 2015 or expiration of the program for those that were not exchanged . in the fourth quarter , t : slim g4 made up majority of our overall shipments . while there is some cannibalization of t : slim , and this high percentage may also reflect some pent up demand , we also believe this trend demonstrates that there is significant interest in this product . we expect that t : slim g4 will represent the largest percentage of our pump shipments in 2016. a substantial portion of the purchase price of an insulin pump is typically paid for by third-party payors , including private insurance companies , preferred provider organizations and other managed care providers . access to adequate coverage and reimbursement for our current and future products by third-party payors is essential to the acceptance of our products by customers . future sales of our current and future products will be limited unless our customers can rely on third-party payors to pay for all or part of the associated purchase cost . in circumstances in which we do not have contracts established with third-party payors , to the extent possible , we utilize our network of national and regional distributors to service our customers . 57 we believe we can achieve profitability because our proprietary technology platform will allow us to maximize efficiencies in the development , production and sale of our products . by offering a family of products , all of which are based on our proprietary technology platform , we believe we can develop and bring to market products more rapidly , while significantly reducing our design and development costs . due to shared product design features , ou r production system is adaptable to new products and we intend to leverage our shared manufacturing infrastructure to reduce our product costs and drive operational efficiencies . further , we expect to continue to increase production volume and to reduce th e per-unit production overhead cost for our pump products and their associated disposable cartridges over time . by expanding our product offerings to address people in different segments of the large and growing insulin-dependent diabetes market , we believ e we can increase the productivity of our sales , clinical and marketing organization , and utilize the expertise of our customer , technical and support services , thereby improving our operating margin . from inception through december 31 , 2015 , we have primarily financed our operations through sales of equity securities , and to a lesser extent , debt financings . we expect to continue to incur net losses for the next several years , and may require additional capital through equity and debt financings in order to fund our operations until we reach a level of revenue adequate to support our cost structure . story_separator_special_tag sales from t : slim pump accounted for 86 % and 90 % of sales , respectively , for the years ended december 31 , 2014 and 2013 , while pump-related supplies primarily accounted for the remainder in each year . sales of accessories were not material in either year . the growth in sales was primarily driven by a 67 % increase in t : slim pump shipments from 6,472 in 2013 to 10,822 in 2014. we expanded the number of sales territories in the united states from 36 at the end of 2013 to 60 at the end of the second quarter of 2014. as a result of our sales force expansion , our field personnel experienced some initial disruption in their sales productivity as their territories were realigned and responsibilities adjusted . 61 sales to distributors accounted for 75 % and 69 % of our total sales for the years ended december 31 , 2014 and 2013 , respectively . the increase in the percentage of our sales to distributors is primarily attributable to certain arrangements between insurance payors and our distributors that becam e effective during the third quarter of 2014. as a result of these arrangements , a portion of our business that previously involved an opportunity to make a direct sale to the customer transitioned to an opportunity to make a sale through a distributor . th e new arrangement afforded certain members easier access to our products as an in-network benefit and provided access to our products to a large portion of members who were previously unable to obtain coverage for our products at all . cost of sales and gross profit . our cost of sales in 2014 was $ 34.5 million , resulting in gross profit of $ 15.2 million , compared to $ 22.8 million in cost of sales and gross profit of $ 6.2 million in 2013. the gross margin in 2014 was 31 % , compared to 21 % in 2013. the improvement in the gross margin was primarily a result of manufacturing efficiencies associated with an increase in production output and improvement in our manufacturing processes . our pump manufacturing overhead spending decreased 19 % while our pump units produced increased 56 % in 2014 compared to 2013 , and our cartridge manufacturing overhead spending increased 40 % while our cartridge units produced increased 143 % in 2014 compared to 2013. included in cost of sales for the year ended december 31 , 2014 were costs of $ 0.4 million associated with our voluntary product recall of selected lots of cartridges initiated in january 2014. the voluntary recall resulted in a less than one percentage point reduction in the gross margin for the year ended december 31 , 2014. by comparison , the 2013 gross margin included $ 1.3 million of recall-associated costs , or a reduction of the gross margin of five percentage points . also included in cost of sales in 2013 were costs of $ 1.1 million that were previously deferred at the end of the fourth quarter of 2012 due to our lack of history for estimating product returns at that time . these costs , along with the previously deferred sales of $ 1.9 million recognized in the first quarter of 2013 , resulted in a two-percentage point increase in gross margin for the year ended december 31 , 2013. selling , general and administrative expenses . sg & a expenses increased 69 % to $ 75.1 million in 2014 from $ 44.5 million in 2013. the increase in sg & a expenses was primarily associated with the expansion of our commercial operations during 2014. as of december 31 , 2014 , our headcount for sales , general and administrative functions increased 43 % compared to december 31 , 2013. this includes an expansion from 36 to 60 territories during 2014 , as well as the growth of the administrative infrastructure to support operations . territories are maintained by sales representatives , field clinical specialists , managed care liaisons , additional sales management and other customer support personnel . employee-related expenses for our sales , general and administrative functions comprise the majority of the sg & a expenses . such employee-related expenses increased $ 24.9 million during 2014 compared to 2013 , including an increase of $ 8.3 million in stock-based compensation associated with equity awards . sg & a expenses also increased $ 5.7 million associated with marketing and promotional activities , tradeshows , travel expenses and facility expansion . research and development expenses . r & d expenses increased 43 % to $ 15.8 million in 2014 from $ 11.1 million in 2013. the increase in r & d expenses in 2014 consisted primarily of an increase of $ 2.5 million in employee-related expenses . at december 31 , 2014 , our headcount for research and development functions increased 17 % compared to december 31 , 2013. the increase in r & d expenses also consisted of a milestone payment of $ 1.0 million to dexcom under our development and commercialization agreement related to our submission of a pma for t : slim g4 to the fda in july 2014. other income ( expense ) . other expense in 2014 was $ 3.8 million , compared to $ 13.7 million in 2013. other expense in 2014 primarily consisted of interest expense associated with the term loan agreement with capital royalty partners in december 2012 and subsequently amended and restated in april 2014 , and further amended in june 2014 , february 2015 and january 2016. we borrowed $ 30 million under the term loan agreement with capital royalty partners in january 2013. in comparison , other expense in 2013 was primarily comprised of $ 9.0 million of expense associated with the revaluation of the fair value of common and preferred stock warrants and $ 4.7 million of interest expense associated with our term loan agreement with capital royalty partners .

