revenues . our revenues for 2019 were $ 996.8 million , a 14 % increase when compared to $ 875.1 million for 2018 , with the increase mainly attributed to the full year impact of the business ink and forte acquisitions , discussed above , which generated an additional $ 91 million of combined revenues in 2019 over that in 2018 , and the remaining increase due primarily to our cloud solutions and managed services arrangements . operating results . operating income for 2019 was $ 126.1 million , or a 12.7 % operating income margin percentage , compared to $ 104.9 million , or a 12.0 % operating income margin percentage for 2018 , with the increase in operating income primarily a result of the higher revenues generated in 2019. diluted earnings per share ( “ eps ” ) . diluted eps for 2019 was $ 2.55 compared to $ 2.01 for 2018 , reflective of the higher operating income for 2019. additionally , 2019 diluted eps was positively impacted by a lower effective income tax rate resulting primarily from an approximately $ 4 million net income tax benefit related to comcast 's exercise of 0.4 million vested common stock warrants . balance sheet and cash flows . as of december 31 , 2019 , we had cash , cash equivalents , and short-term investments of $ 182.7 million , as compared to $ 162.9 million as of december 31 , 2018. cash flows from operating activities for 2019 were $ 151.1 million , compared to $ 143.3 million for 2018. see the liquidity section below for further discussion of our cash flows . 24 significant client relationships comcast . comcast continues to be our largest client . for 2019 and 2018 , revenues from comcast were $ 229 million and $ 221 million , respectively , representing approximately 23 % and 25 % of our total revenues . on december 16 , 2019 , we entered into a new csg master subscriber management system agreement with comcast ( the “ agreement ” ) which supersedes all previous agreements with comcast . the key terms of the agreement are as follows : the agreement is effective january 1 , 2020 , and extends our contractual relationship with comcast through december 31 , 2024 for cloud and related solutions , and through december 31 , 2025 for print and mail services for residential customer accounts . in addition , the agreement provides comcast with the option to extend the cloud and related services for one additional year by exercising the renewal option no later than june 30 , 2023. we maintain the exclusive right to provide print and mail services to all comcast residential customer accounts through december 31 , 2025. the fees to be generated under the agreement will be based primarily on monthly charges for cloud and related services per comcast residential customer account , and various other ancillary services based on actual usage . certain of the per-unit fees include volume-based pricing tiers , and may be subject to annual price escalators . the agreement contains certain financial commitments associated with the number of comcast residential customer accounts that are to be processed on our systems , with such commitments decreasing over the life of the agreement . however , if comcast chooses to process fewer customer accounts on our systems than the committed amounts , the monthly fees to be paid by comcast will be based on the higher number of committed customer accounts for the applicable billing period . the agreement includes potential financial incentives related to comcast 's efficient use of our systems . the agreement contains certain rights and obligations of both parties , including the following key items : ( i ) the termination of the agreement under certain conditions ; ( ii ) various service level commitments ; and ( iii ) remedies and limitation on liabilities associated with specified breaches of contractual obligations . when compared to the previous agreement , we provided overall pricing adjustments of approximately 10 % to comcast , which in effect , will reduce the current fees we will receive from comcast . the anticipated revenue impact in both the near and long terms may vary depending on the type of service consumed by comcast . the impact from the agreement is only an estimate and actual results may vary depending upon a variety of factors . we undertake no duty to update or revise any forward-looking statements , whether as a result of new information , future events or otherwise . a copy of the agreement , with confidential information redacted , is filed as exhibit 10.27 to this form 10-k. charter . charter is our second largest client . for 2019 and 2018 , revenues from charter were $ 195 million and $ 179 million , respectively , representing approximately 20 % of our total revenues for both years . our agreement with charter runs through december 31 , 2021 , with an option to extend the agreement for an additional one-year term . a copy of the charter agreements and related amendments , with confidential information redacted , are included in the exhibits to our periodic filings with the sec . stock-based compensation expense stock-based compensation expense is included in the following ( in thousands ) : replace_table_token_6_th see notes 2 and 13 to our financial statements for additional discussion of our stock-based compensation expense . 25 amortization of acquired intangible assets amortization of acquired intangible assets is included in the following ( in thousands ) : replace_table_token_7_th the increases in amortization of acquired intangible assets between years are due to the amortization of the intangible assets acquired with the business ink and forte acquisitions in 2018 , discussed above , thus 2019 having the full year impact . see note 4 to our financial statements for additional discussion of our acquired intangible assets and related amortization . story_separator_special_tag cost of software and services ( exclusive of depreciation ) . the cost of software and services revenues consists principally of the following : ( i ) professional services organization ; ( ii ) various product support organizations ( e.g . , delivery , etc . ) ; ( iii ) facilities and infrastructure costs related to these organizations ; and ( iv ) third-party software costs and or royalties related to certain software products . the costs related to new solution development ( including significant enhancements to existing solutions and services ) are included in r & d expense . the cost of software and services for 2019 was $ 31.7 million , a 9 % decrease when compared to $ 34.9 million for 2018. this decrease is reflective of the lower software and services revenues and as a result , personnel and the related costs previously allocated to professional services projects have been reassigned to other areas of the business . total cost of software and services as a percentage of our software and services revenues for 2019 , 2018 , and 2017 were 60.6 % , 60.0 % , and 62.0 % , respectively . variability in quarterly revenues and operating results are inherent characteristics of companies that sell software licenses and perform professional services . our quarterly revenues for software licenses and professional services may fluctuate , depending on various factors , including the timing of executed contracts and revenue recognition , and the delivery of contracted solutions . however , the costs associated with software and professional services revenues are not subject to the same degree of variability ( e.g . , these costs are generally fixed in nature within a relatively short period of time ) , and thus , fluctuations in our cost of software and services as a percentage of our software and services revenues will likely occur between periods . cost of maintenance ( exclusive of depreciation ) . the cost of maintenance consists principally of the following : ( i ) client support organizations ( e.g . , our client support call center , account management , etc . ) ; ( ii ) various product support organizations ( e.g . , product maintenance , product management , etc . ) ; ( iii ) facilities and infrastructure costs related to these organizations ; and ( iv ) amortization of acquired intangibles . the cost of maintenance for 2019 decreased 5 % to $ 21.0 million , from $ 22.1 million for 2018 , with the decrease primarily due to lower amortization expense for certain acquired intangible assets . total cost of maintenance as a percentage of our maintenance revenues for 2019 , 2018 , and 2017 were 43.5 % , 43.8 % , and 53.9 % , respectively . 29 r & d expense ( exclusive of depreciation ) . r & d expense for 2019 was $ 128.0 million , a 3 % increase when compared to $ 124.0 million for 2018 , with the increase mainly attributed to the r & d costs associated with the acquired forte business . our r & d efforts are focused on the continued evolution of our solutions that enable global service providers worldwide to provide a more personalized customer experience while introducing new digital products and services . this includes the continued investment in our cloud-based solutions . as a percentage of total revenues , r & d expense for 2019 , 2018 , and 2017 was 12.8 % , 14.2 % , and 14.3 % , respectively ( with the percentage decrease in 2019 reflective of a full year of transaction fees of $ 69.1 million ) . we anticipate the level of r & d investment in the near-term to be relatively consistent with 2019. selling , general and administrative expense ( “ sg & a ” ) ( exclusive of depreciation ) . sg & a expense for 2019 increased 13 % to $ 191.3 million , from $ 169.3 million for 2018. the increase in sg & a expense between 2019 and 2018 is primarily due to the sg & a costs related to the acquired forte business , and an increase in employee-related costs . as a percentage of total revenues , sg & a expense for 2019 , 2018 , and 2017 was 19.2 % , 19.3 % and 19.5 % , respectively . depreciation expense . depreciation expense for all property and equipment is reflected separately in the aggregate and is not included in the cost of revenues or the other components of operating expenses . depreciation expense for 2019 was $ 21.4 million , a 17 % increase from $ 18.3 million for 2018. the increase can be primarily attributed to depreciation expense from the acquired business ink and forte assets and the full year impact of our increased level of capital expenditures during 2018. restructuring and reorganization charges . in 2019 and 2018 , we implemented various cost reduction and efficiency initiatives that resulted in restructuring and reorganization charges of $ 4.8 million and $ 8.7 million , respectively . these initiatives included : ( i ) reducing and reorganizing our workforce to further align it around our long-term growth initiatives ; ( ii ) the abandonment of space at some of our facility locations ; and ( iii ) the reversal of a liability related to a previous disposition of a business . see note 8 to our financial statements for additional information regarding these initiatives . operating income . operating income and operating income margin for 2019 was $ 126.1 million , or 12.7 % of total revenues , compared to $ 104.9 million , or 12.0 % of total revenues for 2018. the increase in operating income can be primarily attributed to the higher revenues generated in 2019. interest expense and amortization of original issue discount ( “ oid ” ) . our interest expense relates primarily to

cash dividends paid on common stock during 2019 and 2018 , the board approved dividend payments totaling $ 29.4 million and $ 28.1 million , respectively , of which $ 29.1 million and $ 28.0 million , respectively , had been paid through december 31 , 2019 and 2018 ( with the differences attributed to unvested incentive shares that are paid upon vesting ) . common stock warrants during the fourth quarter of 2019 , comcast exercised the remaining 0.4 million of their vested common stock warrants , which we net cash settled under the provisions of the warrant agreement for $ 12.9 million . see note 12 to our financial statements for further discussion of comcast 's exercise of their common stock warrants . long-term debt during the first quarter of 2018 , we refinanced our 2015 credit agreement and as a result , we repaid the outstanding principal balance of $ 120.0 million and borrowed $ 150.0 million under the 2018 credit agreement , resulting in a net increase of available cash of $ 30.0 million . as part of the refinancing , we paid $ 1.5 million of deferred financing costs . additionally , during 2019 and 2018 , we made principal repayments of $ 7.5 million and $ 5.6 million , respectively , on our long-term debt balance . see note 5 to our financial statements for additional discussion of our long-term debt . 34 contractual obligations and other commercial commitments and contingencies we have various contractual obligations that are recorded as liabilities in our consolidated balance sheets . other items , such as certain purchase commitments and other executory contracts , are not recognized as liabilities in our balance sheets but are required to be disclosed . the following table summarizes our significant contractual obligations and commercial commitments as of december 31 , 2019 , and the future periods in which such obligations are expected to be settled in cash ( in thousands ) .


 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.
     ```cash dividends paid on common stock during 2019 and 2018 , the board approved dividend payments totaling $ 29.4 million and $ 28.1 million , respectively , of which $ 29.1 million and $ 28.0 million , respectively , had been paid through december 31 , 2019 and 2018 ( with the differences attributed to unvested incentive shares that are paid upon vesting ) . common stock warrants during the fourth quarter of 2019 , comcast exercised the remaining 0.4 million of their vested common stock warrants , which we net cash settled under the provisions of the warrant agreement for $ 12.9 million . see note 12 to our financial statements for further discussion of comcast 's exercise of their common stock warrants . long-term debt during the first quarter of 2018 , we refinanced our 2015 credit agreement and as a result , we repaid the outstanding principal balance of $ 120.0 million and borrowed $ 150.0 million under the 2018 credit agreement , resulting in a net increase of available cash of $ 30.0 million . as part of the refinancing , we paid $ 1.5 million of deferred financing costs . additionally , during 2019 and 2018 , we made principal repayments of $ 7.5 million and $ 5.6 million , respectively , on our long-term debt balance . see note 5 to our financial statements for additional discussion of our long-term debt . 34 contractual obligations and other commercial commitments and contingencies we have various contractual obligations that are recorded as liabilities in our consolidated balance sheets . other items , such as certain purchase commitments and other executory contracts , are not recognized as liabilities in our balance sheets but are required to be disclosed . the following table summarizes our significant contractual obligations and commercial commitments as of december 31 , 2019 , and the future periods in which such obligations are expected to be settled in cash ( in thousands ) .
```    
 Suspicious Activity Report : revenues . our revenues for 2019 were $ 996.8 million , a 14 % increase when compared to $ 875.1 million for 2018 , with the increase mainly attributed to the full year impact of the business ink and forte acquisitions , discussed above , which generated an additional $ 91 million of combined revenues in 2019 over that in 2018 , and the remaining increase due primarily to our cloud solutions and managed services arrangements . operating results . operating income for 2019 was $ 126.1 million , or a 12.7 % operating income margin percentage , compared to $ 104.9 million , or a 12.0 % operating income margin percentage for 2018 , with the increase in operating income primarily a result of the higher revenues generated in 2019. diluted earnings per share ( “ eps ” ) . diluted eps for 2019 was $ 2.55 compared to $ 2.01 for 2018 , reflective of the higher operating income for 2019. additionally , 2019 diluted eps was positively impacted by a lower effective income tax rate resulting primarily from an approximately $ 4 million net income tax benefit related to comcast 's exercise of 0.4 million vested common stock warrants . balance sheet and cash flows . as of december 31 , 2019 , we had cash , cash equivalents , and short-term investments of $ 182.7 million , as compared to $ 162.9 million as of december 31 , 2018. cash flows from operating activities for 2019 were $ 151.1 million , compared to $ 143.3 million for 2018. see the liquidity section below for further discussion of our cash flows . 24 significant client relationships comcast . comcast continues to be our largest client . for 2019 and 2018 , revenues from comcast were $ 229 million and $ 221 million , respectively , representing approximately 23 % and 25 % of our total revenues . on december 16 , 2019 , we entered into a new csg master subscriber management system agreement with comcast ( the “ agreement ” ) which supersedes all previous agreements with comcast . the key terms of the agreement are as follows : the agreement is effective january 1 , 2020 , and extends our contractual relationship with comcast through december 31 , 2024 for cloud and related solutions , and through december 31 , 2025 for print and mail services for residential customer accounts . in addition , the agreement provides comcast with the option to extend the cloud and related services for one additional year by exercising the renewal option no later than june 30 , 2023. we maintain the exclusive right to provide print and mail services to all comcast residential customer accounts through december 31 , 2025. the fees to be generated under the agreement will be based primarily on monthly charges for cloud and related services per comcast residential customer account , and various other ancillary services based on actual usage . certain of the per-unit fees include volume-based pricing tiers , and may be subject to annual price escalators . the agreement contains certain financial commitments associated with the number of comcast residential customer accounts that are to be processed on our systems , with such commitments decreasing over the life of the agreement . however , if comcast chooses to process fewer customer accounts on our systems than the committed amounts , the monthly fees to be paid by comcast will be based on the higher number of committed customer accounts for the applicable billing period . the agreement includes potential financial incentives related to comcast 's efficient use of our systems . the agreement contains certain rights and obligations of both parties , including the following key items : ( i ) the termination of the agreement under certain conditions ; ( ii ) various service level commitments ; and ( iii ) remedies and limitation on liabilities associated with specified breaches of contractual obligations . when compared to the previous agreement , we provided overall pricing adjustments of approximately 10 % to comcast , which in effect , will reduce the current fees we will receive from comcast . the anticipated revenue impact in both the near and long terms may vary depending on the type of service consumed by comcast . the impact from the agreement is only an estimate and actual results may vary depending upon a variety of factors . we undertake no duty to update or revise any forward-looking statements , whether as a result of new information , future events or otherwise . a copy of the agreement , with confidential information redacted , is filed as exhibit 10.27 to this form 10-k. charter . charter is our second largest client . for 2019 and 2018 , revenues from charter were $ 195 million and $ 179 million , respectively , representing approximately 20 % of our total revenues for both years . our agreement with charter runs through december 31 , 2021 , with an option to extend the agreement for an additional one-year term . a copy of the charter agreements and related amendments , with confidential information redacted , are included in the exhibits to our periodic filings with the sec . stock-based compensation expense stock-based compensation expense is included in the following ( in thousands ) : replace_table_token_6_th see notes 2 and 13 to our financial statements for additional discussion of our stock-based compensation expense . 25 amortization of acquired intangible assets amortization of acquired intangible assets is included in the following ( in thousands ) : replace_table_token_7_th the increases in amortization of acquired intangible assets between years are due to the amortization of the intangible assets acquired with the business ink and forte acquisitions in 2018 , discussed above , thus 2019 having the full year impact . see note 4 to our financial statements for additional discussion of our acquired intangible assets and related amortization . story_separator_special_tag cost of software and services ( exclusive of depreciation ) . the cost of software and services revenues consists principally of the following : ( i ) professional services organization ; ( ii ) various product support organizations ( e.g . , delivery , etc . ) ; ( iii ) facilities and infrastructure costs related to these organizations ; and ( iv ) third-party software costs and or royalties related to certain software products . the costs related to new solution development ( including significant enhancements to existing solutions and services ) are included in r & d expense . the cost of software and services for 2019 was $ 31.7 million , a 9 % decrease when compared to $ 34.9 million for 2018. this decrease is reflective of the lower software and services revenues and as a result , personnel and the related costs previously allocated to professional services projects have been reassigned to other areas of the business . total cost of software and services as a percentage of our software and services revenues for 2019 , 2018 , and 2017 were 60.6 % , 60.0 % , and 62.0 % , respectively . variability in quarterly revenues and operating results are inherent characteristics of companies that sell software licenses and perform professional services . our quarterly revenues for software licenses and professional services may fluctuate , depending on various factors , including the timing of executed contracts and revenue recognition , and the delivery of contracted solutions . however , the costs associated with software and professional services revenues are not subject to the same degree of variability ( e.g . , these costs are generally fixed in nature within a relatively short period of time ) , and thus , fluctuations in our cost of software and services as a percentage of our software and services revenues will likely occur between periods . cost of maintenance ( exclusive of depreciation ) . the cost of maintenance consists principally of the following : ( i ) client support organizations ( e.g . , our client support call center , account management , etc . ) ; ( ii ) various product support organizations ( e.g . , product maintenance , product management , etc . ) ; ( iii ) facilities and infrastructure costs related to these organizations ; and ( iv ) amortization of acquired intangibles . the cost of maintenance for 2019 decreased 5 % to $ 21.0 million , from $ 22.1 million for 2018 , with the decrease primarily due to lower amortization expense for certain acquired intangible assets . total cost of maintenance as a percentage of our maintenance revenues for 2019 , 2018 , and 2017 were 43.5 % , 43.8 % , and 53.9 % , respectively . 29 r & d expense ( exclusive of depreciation ) . r & d expense for 2019 was $ 128.0 million , a 3 % increase when compared to $ 124.0 million for 2018 , with the increase mainly attributed to the r & d costs associated with the acquired forte business . our r & d efforts are focused on the continued evolution of our solutions that enable global service providers worldwide to provide a more personalized customer experience while introducing new digital products and services . this includes the continued investment in our cloud-based solutions . as a percentage of total revenues , r & d expense for 2019 , 2018 , and 2017 was 12.8 % , 14.2 % , and 14.3 % , respectively ( with the percentage decrease in 2019 reflective of a full year of transaction fees of $ 69.1 million ) . we anticipate the level of r & d investment in the near-term to be relatively consistent with 2019. selling , general and administrative expense ( “ sg & a ” ) ( exclusive of depreciation ) . sg & a expense for 2019 increased 13 % to $ 191.3 million , from $ 169.3 million for 2018. the increase in sg & a expense between 2019 and 2018 is primarily due to the sg & a costs related to the acquired forte business , and an increase in employee-related costs . as a percentage of total revenues , sg & a expense for 2019 , 2018 , and 2017 was 19.2 % , 19.3 % and 19.5 % , respectively . depreciation expense . depreciation expense for all property and equipment is reflected separately in the aggregate and is not included in the cost of revenues or the other components of operating expenses . depreciation expense for 2019 was $ 21.4 million , a 17 % increase from $ 18.3 million for 2018. the increase can be primarily attributed to depreciation expense from the acquired business ink and forte assets and the full year impact of our increased level of capital expenditures during 2018. restructuring and reorganization charges . in 2019 and 2018 , we implemented various cost reduction and efficiency initiatives that resulted in restructuring and reorganization charges of $ 4.8 million and $ 8.7 million , respectively . these initiatives included : ( i ) reducing and reorganizing our workforce to further align it around our long-term growth initiatives ; ( ii ) the abandonment of space at some of our facility locations ; and ( iii ) the reversal of a liability related to a previous disposition of a business . see note 8 to our financial statements for additional information regarding these initiatives . operating income . operating income and operating income margin for 2019 was $ 126.1 million , or 12.7 % of total revenues , compared to $ 104.9 million , or 12.0 % of total revenues for 2018. the increase in operating income can be primarily attributed to the higher revenues generated in 2019. interest expense and amortization of original issue discount ( “ oid ” ) . our interest expense relates primarily to

