33 key financial metrics and drivers as discussed in the previous section , we utilize a portfolio of key financial metrics to manage the company , including gaap and non-gaap measures . as detailed below , we review revenues by type and by segment , or by major product line . we also review expenses by activity , which provides more transparency into how resources are being deployed . in addition , we utilize operating metrics including run rate , subscription sales and retention rate to analyze past performance and to provide insight into our latest reported portfolio of recurring business . in the discussion that follows , we provide certain variances excluding the impact of foreign currency exchange rate fluctuations . foreign currency exchange rate fluctuations reflect the difference between the current period results as reported compared to the current period results recalculated using the foreign currency exchange rates in effect for the comparable prior period . while operating revenues adjusted for the impact of foreign currency fluctuations includes asset-based fees that have been adjusted for the impact of foreign currency fluctuations , the underlying aum , which is the primary component of asset-based fees , is not adjusted for foreign currency fluctuations . approximately two-thirds of the aum are invested in securities denominated in currencies other than the u.s. dollar , and accordingly , any such impact is excluded from the disclosed foreign currency-adjusted variances . revenues our revenues are characterized by type , which broadly reflects the nature of how they are recognized or earned . our revenue types are recurring subscription , asset-based fees and non-recurring revenues . we also group our revenues by segment and provide the revenue type within each segment . recurring subscription revenues represent fees earned from clients primarily under renewable contracts and are generally recognized ratably over the term of the license or service pursuant to the contract terms . the fees are recognized as we provide the product and service to the client over the license period and are generally billed in advance , prior to the license start date . asset-based fees represent fees earned on the aum linked to our indexes from independent third-party sources or the most recently reported information provided by the client . asset-based fees also include revenues related to futures and options contracts linked to our indexes , which are primarily based on trading volumes . non-recurring revenues primarily represent fees earned on products and services where we do not have renewal contracts and primarily include revenues for providing historical data , certain implementation services and other special client requests , which are generally recognized at a point in time . operating expenses we group our operating expenses into the following activity categories : cost of revenues ; selling and marketing ; research and development ( “ r & d ” ) ; general and administrative ( “ g & a ” ) ; amortization of intangible assets ; and depreciation and amortization of property , equipment and leasehold improvements . costs are assigned to these activity categories based on the nature of the expense or , when not directly attributable , an estimated allocation based on the type of effort involved . 34 cost of revenues cost of revenues expenses consist of costs related to the production and servicing of our products and services and primarily includes related information technology costs , including data center , platform and infrastructure costs ; costs to acquire , produce and maintain market data information ; costs of research to support and maintain existing products ; costs of product management teams ; costs of client service and consultant teams to support customer needs ; as well as other support costs directly attributable to the cost of revenues including certain human resources , finance and legal costs . selling and marketing selling and marketing expenses consist of costs associated with acquiring new clients or selling new products or product renewals to existing clients and primarily includes the costs of our sales and marketing teams , as well as costs incurred in other groups associated with acquiring new business , including product management , research , technology and sales operations . research and development r & d expenses consist of costs to develop new or enhance existing products and costs to develop new or improved technology and service platforms for the delivery of our products and services and primarily include the costs of development , research , product management , project management and the technology support associated with these efforts . general and administrative g & a expenses consist of costs primarily related to finance operations , human resources , office of the ceo , legal , corporate technology , corporate development and certain other administrative costs that are not directly attributed , but are instead allocated , to a product or service . amortization of intangible assets amortization of intangible assets expense relates to definite-lived intangible assets arising from past acquisitions and internal capitalized software projects . intangibles arising from past acquisitions consist of customer relationships , trademarks and trade names , technology and software , proprietary processes and data and non-competition agreements . we amortize definite-lived intangible assets over their estimated useful lives . definite-lived intangible assets are tested for impairment when impairment indicators are present , and , if impaired , written down to fair value based on either discounted cash flows or appraised values . we have no indefinite-lived intangible assets . depreciation and amortization of property , equipment and leasehold improvements this category consists of expenses related to depreciating or amortizing the cost of furniture and fixtures , computer and related equipment and leasehold improvements over the estimated useful life of the assets . story_separator_special_tag depreciation and amortization of property , equipment and leasehold improvements depreciation and amortization of property , equipment and leasehold improvements for the year ended december 31 , 2019 and 2018 was $ 30.0 million and $ 31.3 million , respectively . other expense ( income ) , net other expense ( income ) , net for the year ended december 31 , 2019 increased 167.3 % to $ 152.4 million compared to $ 57.0 million for the year ended december 31 , 2018. the increase was primarily driven by the absence of the $ 46.6 million and $ 10.6 million of gains realized from the investorforce and fea divestitures , respectively , which occurred in 2018. the increase was also driven by the $ 16.8 million loss on extinguishment associated with the partial pre-maturity redemption of the 2024 senior notes which included approximately $ 13.1 million of call premium paid in accordance with the redemption prices set forth in the indenture and the write-off of approximately $ 3.7 million of unamortized costs associated with the 2024 senior notes . in addition , the increase also reflects higher interest expense associated with higher outstanding debt and higher foreign currency exchange losses . income taxes the provision for income tax decreased 67.5 % to $ 39.7 million for the year ended december 31 , 2019 compared to $ 122.0 million for the year ended december 31 , 2018. these amounts reflect effective tax rates of 6.6 % and 19.4 % for the years ended december 31 , 2019 and 2018 , respectively . the effective tax rate of 6.6 % for the year ended december 31 , 2019 reflects the impact of certain favorable discrete items totaling $ 85.7 million . these discrete items primarily relate to $ 66.6 million of excess tax benefits recognized upon vesting of the 2016 multi-year psus and $ 16.1 million of excess tax benefits on other share-based compensation recognized during the period . in addition , the effective tax rate was impacted by a beneficial geographic mix of earnings . the effective tax rate of 19.4 % for the year ended december 31 , 2018 reflects the impact of certain favorable discrete items totaling $ 31.9 million . these discrete items include $ 8.8 million of excess tax benefits related to stock-based compensation , $ 11.9 million related to the release of valuation allowances previously recorded on capital loss carryforwards and $ 11.2 million related to the final impact of tax reform . 42 net income as a result of the factors described above , net income for the year ended december 31 , 2019 increased 11.0 % to $ 563.6 million compared to $ 507.9 million for the year ended december 31 , 2018. adjusted ebitda the following table presents the calculation of the non-gaap adjusted ebitda measure for the years indicated : replace_table_token_12_th adjusted ebitda increased 10.1 % to $ 850.5 million for the year ended december 31 , 2019 compared to $ 772.4 million for the year ended december 31 , 2018. adjusted ebitda margin increased to 54.6 % for the year ended december 31 , 2019 compared to 53.9 % for the year ended december 31 , 2018. the increase in adjusted ebitda margin reflects a higher rate of growth in operating revenues as compared to the rate of growth of adjusted ebitda expenses . reconciliation of adjusted ebitda to net income and adjusted ebitda expenses to operating expenses the following table presents the reconciliation of adjusted ebitda to net income for the years indicated : replace_table_token_13_th 43 the following table presents the reconciliation of adjusted ebitda expenses to operating expenses for the years indicated : replace_table_token_14_th segment results the results for each of our three reportable segments for the years ended december 31 , 2019 and 2018 are presented below : index segment the following table presents the results for the index segment for the years indicated : replace_table_token_15_th revenues related to index products increased 10.2 % to $ 920.9 million for the year ended december 31 , 2019 compared to $ 835.5 million for the year ended december 31 , 2018. revenues from recurring subscriptions were up 11.2 % to $ 531.0 million for the year ended december 31 , 2019 compared to $ 477.6 million for the year ended december 31 , 2018. the increase was driven by strong growth in core developed market modules , factor and esg index products and emerging market modules . the impact of foreign currency exchange rate fluctuations on revenues from recurring subscriptions was negligible . 44 revenues from asset-based fees increased 7.5 % to $ 361.9 million for the year ended december 31 , 2019 compared to $ 336.6 million for the year ended december 31 , 2018. the increase in asset-based fees was primarily driven by an increase in revenues from exchange traded futures and options contracts linked to msci indexes . the increase in revenues from futures and options contracts was driven by approximately $ 5.0 million in additional fees associated with prior periods attributed to a retrospective price increase from a renegotiated contract entered into during the year ended december 31 , 2019 , as well as the cumulative impact of price and volume increases . the increase in revenues from asset-based fees was also driven by higher revenues from etfs linked to msci indexes , which was driven by a 7 . 6 % increase in average aum , partially offset by the impact of a change in product mix . in addition , the increase in revenues from asset-based fees was driven by higher revenues from non-etf passive products linked to msci indexes . the impact of foreign currency exchange rate fluctuations on revenues from asset-based fees was negligible . index segment adjusted ebitda expenses increased 10.2 % to $ 250.7 million for the year ended december 31 , 2019 compared to $ 227.6 million for the year ended december 31 , 2018 , reflecting higher expenses

liquidity and capital resources we require capital to fund ongoing operations , internal growth initiatives and acquisitions . our primary sources of liquidity are cash flows generated from our operations , existing cash and cash equivalents and credit capacity under our existing credit facilities . in addition , we believe we have access to additional funding in the public and private markets . we intend to use these sources of liquidity to , among other things , service our existing and future debt obligations , fund our working capital requirements for capital expenditures , investments , acquisitions , dividend payments and repurchases of our common stock . in connection with our business strategy , we regularly evaluate acquisition and strategic partnership opportunities . we believe our liquidity , along with other financing alternatives , will provide the necessary capital to fund these transactions and achieve our planned growth . senior notes and credit agreement we have an aggregate of $ 3,100.0 million in senior unsecured notes ( collectively , the “ senior notes ” ) consisting of five discrete private placement offerings and entered into a $ 400.0 million revolving credit agreement with a syndicate of banks . see note 5 , “ commitments and contingencies , ” of the notes to consolidated financial statements included herein for additional information on our senior notes and revolving credit agreement . the senior notes and the revolving credit agreement are fully and unconditionally , and jointly and severally , guaranteed by our direct or indirect wholly-owned domestic subsidiaries that account for more than 5 % of our and our subsidiaries ' consolidated assets , other than certain excluded subsidiaries ( the “ subsidiary guarantors ” ) . amounts due under the revolving credit agreement are our and the subsidiary guarantors ' senior unsecured obligations and rank equally with the senior notes and any of our other unsecured , unsubordinated debt , senior to any of our subordinated debt and effectively subordinated to our secured debt to the extent of the assets securing such debt .


 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 we require capital to fund ongoing operations , internal growth initiatives and acquisitions . our primary sources of liquidity are cash flows generated from our operations , existing cash and cash equivalents and credit capacity under our existing credit facilities . in addition , we believe we have access to additional funding in the public and private markets . we intend to use these sources of liquidity to , among other things , service our existing and future debt obligations , fund our working capital requirements for capital expenditures , investments , acquisitions , dividend payments and repurchases of our common stock . in connection with our business strategy , we regularly evaluate acquisition and strategic partnership opportunities . we believe our liquidity , along with other financing alternatives , will provide the necessary capital to fund these transactions and achieve our planned growth . senior notes and credit agreement we have an aggregate of $ 3,100.0 million in senior unsecured notes ( collectively , the “ senior notes ” ) consisting of five discrete private placement offerings and entered into a $ 400.0 million revolving credit agreement with a syndicate of banks . see note 5 , “ commitments and contingencies , ” of the notes to consolidated financial statements included herein for additional information on our senior notes and revolving credit agreement . the senior notes and the revolving credit agreement are fully and unconditionally , and jointly and severally , guaranteed by our direct or indirect wholly-owned domestic subsidiaries that account for more than 5 % of our and our subsidiaries ' consolidated assets , other than certain excluded subsidiaries ( the “ subsidiary guarantors ” ) . amounts due under the revolving credit agreement are our and the subsidiary guarantors ' senior unsecured obligations and rank equally with the senior notes and any of our other unsecured , unsubordinated debt , senior to any of our subordinated debt and effectively subordinated to our secured debt to the extent of the assets securing such debt .
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 Suspicious Activity Report : 33 key financial metrics and drivers as discussed in the previous section , we utilize a portfolio of key financial metrics to manage the company , including gaap and non-gaap measures . as detailed below , we review revenues by type and by segment , or by major product line . we also review expenses by activity , which provides more transparency into how resources are being deployed . in addition , we utilize operating metrics including run rate , subscription sales and retention rate to analyze past performance and to provide insight into our latest reported portfolio of recurring business . in the discussion that follows , we provide certain variances excluding the impact of foreign currency exchange rate fluctuations . foreign currency exchange rate fluctuations reflect the difference between the current period results as reported compared to the current period results recalculated using the foreign currency exchange rates in effect for the comparable prior period . while operating revenues adjusted for the impact of foreign currency fluctuations includes asset-based fees that have been adjusted for the impact of foreign currency fluctuations , the underlying aum , which is the primary component of asset-based fees , is not adjusted for foreign currency fluctuations . approximately two-thirds of the aum are invested in securities denominated in currencies other than the u.s. dollar , and accordingly , any such impact is excluded from the disclosed foreign currency-adjusted variances . revenues our revenues are characterized by type , which broadly reflects the nature of how they are recognized or earned . our revenue types are recurring subscription , asset-based fees and non-recurring revenues . we also group our revenues by segment and provide the revenue type within each segment . recurring subscription revenues represent fees earned from clients primarily under renewable contracts and are generally recognized ratably over the term of the license or service pursuant to the contract terms . the fees are recognized as we provide the product and service to the client over the license period and are generally billed in advance , prior to the license start date . asset-based fees represent fees earned on the aum linked to our indexes from independent third-party sources or the most recently reported information provided by the client . asset-based fees also include revenues related to futures and options contracts linked to our indexes , which are primarily based on trading volumes . non-recurring revenues primarily represent fees earned on products and services where we do not have renewal contracts and primarily include revenues for providing historical data , certain implementation services and other special client requests , which are generally recognized at a point in time . operating expenses we group our operating expenses into the following activity categories : cost of revenues ; selling and marketing ; research and development ( “ r & d ” ) ; general and administrative ( “ g & a ” ) ; amortization of intangible assets ; and depreciation and amortization of property , equipment and leasehold improvements . costs are assigned to these activity categories based on the nature of the expense or , when not directly attributable , an estimated allocation based on the type of effort involved . 34 cost of revenues cost of revenues expenses consist of costs related to the production and servicing of our products and services and primarily includes related information technology costs , including data center , platform and infrastructure costs ; costs to acquire , produce and maintain market data information ; costs of research to support and maintain existing products ; costs of product management teams ; costs of client service and consultant teams to support customer needs ; as well as other support costs directly attributable to the cost of revenues including certain human resources , finance and legal costs . selling and marketing selling and marketing expenses consist of costs associated with acquiring new clients or selling new products or product renewals to existing clients and primarily includes the costs of our sales and marketing teams , as well as costs incurred in other groups associated with acquiring new business , including product management , research , technology and sales operations . research and development r & d expenses consist of costs to develop new or enhance existing products and costs to develop new or improved technology and service platforms for the delivery of our products and services and primarily include the costs of development , research , product management , project management and the technology support associated with these efforts . general and administrative g & a expenses consist of costs primarily related to finance operations , human resources , office of the ceo , legal , corporate technology , corporate development and certain other administrative costs that are not directly attributed , but are instead allocated , to a product or service . amortization of intangible assets amortization of intangible assets expense relates to definite-lived intangible assets arising from past acquisitions and internal capitalized software projects . intangibles arising from past acquisitions consist of customer relationships , trademarks and trade names , technology and software , proprietary processes and data and non-competition agreements . we amortize definite-lived intangible assets over their estimated useful lives . definite-lived intangible assets are tested for impairment when impairment indicators are present , and , if impaired , written down to fair value based on either discounted cash flows or appraised values . we have no indefinite-lived intangible assets . depreciation and amortization of property , equipment and leasehold improvements this category consists of expenses related to depreciating or amortizing the cost of furniture and fixtures , computer and related equipment and leasehold improvements over the estimated useful life of the assets . story_separator_special_tag depreciation and amortization of property , equipment and leasehold improvements depreciation and amortization of property , equipment and leasehold improvements for the year ended december 31 , 2019 and 2018 was $ 30.0 million and $ 31.3 million , respectively . other expense ( income ) , net other expense ( income ) , net for the year ended december 31 , 2019 increased 167.3 % to $ 152.4 million compared to $ 57.0 million for the year ended december 31 , 2018. the increase was primarily driven by the absence of the $ 46.6 million and $ 10.6 million of gains realized from the investorforce and fea divestitures , respectively , which occurred in 2018. the increase was also driven by the $ 16.8 million loss on extinguishment associated with the partial pre-maturity redemption of the 2024 senior notes which included approximately $ 13.1 million of call premium paid in accordance with the redemption prices set forth in the indenture and the write-off of approximately $ 3.7 million of unamortized costs associated with the 2024 senior notes . in addition , the increase also reflects higher interest expense associated with higher outstanding debt and higher foreign currency exchange losses . income taxes the provision for income tax decreased 67.5 % to $ 39.7 million for the year ended december 31 , 2019 compared to $ 122.0 million for the year ended december 31 , 2018. these amounts reflect effective tax rates of 6.6 % and 19.4 % for the years ended december 31 , 2019 and 2018 , respectively . the effective tax rate of 6.6 % for the year ended december 31 , 2019 reflects the impact of certain favorable discrete items totaling $ 85.7 million . these discrete items primarily relate to $ 66.6 million of excess tax benefits recognized upon vesting of the 2016 multi-year psus and $ 16.1 million of excess tax benefits on other share-based compensation recognized during the period . in addition , the effective tax rate was impacted by a beneficial geographic mix of earnings . the effective tax rate of 19.4 % for the year ended december 31 , 2018 reflects the impact of certain favorable discrete items totaling $ 31.9 million . these discrete items include $ 8.8 million of excess tax benefits related to stock-based compensation , $ 11.9 million related to the release of valuation allowances previously recorded on capital loss carryforwards and $ 11.2 million related to the final impact of tax reform . 42 net income as a result of the factors described above , net income for the year ended december 31 , 2019 increased 11.0 % to $ 563.6 million compared to $ 507.9 million for the year ended december 31 , 2018. adjusted ebitda the following table presents the calculation of the non-gaap adjusted ebitda measure for the years indicated : replace_table_token_12_th adjusted ebitda increased 10.1 % to $ 850.5 million for the year ended december 31 , 2019 compared to $ 772.4 million for the year ended december 31 , 2018. adjusted ebitda margin increased to 54.6 % for the year ended december 31 , 2019 compared to 53.9 % for the year ended december 31 , 2018. the increase in adjusted ebitda margin reflects a higher rate of growth in operating revenues as compared to the rate of growth of adjusted ebitda expenses . reconciliation of adjusted ebitda to net income and adjusted ebitda expenses to operating expenses the following table presents the reconciliation of adjusted ebitda to net income for the years indicated : replace_table_token_13_th 43 the following table presents the reconciliation of adjusted ebitda expenses to operating expenses for the years indicated : replace_table_token_14_th segment results the results for each of our three reportable segments for the years ended december 31 , 2019 and 2018 are presented below : index segment the following table presents the results for the index segment for the years indicated : replace_table_token_15_th revenues related to index products increased 10.2 % to $ 920.9 million for the year ended december 31 , 2019 compared to $ 835.5 million for the year ended december 31 , 2018. revenues from recurring subscriptions were up 11.2 % to $ 531.0 million for the year ended december 31 , 2019 compared to $ 477.6 million for the year ended december 31 , 2018. the increase was driven by strong growth in core developed market modules , factor and esg index products and emerging market modules . the impact of foreign currency exchange rate fluctuations on revenues from recurring subscriptions was negligible . 44 revenues from asset-based fees increased 7.5 % to $ 361.9 million for the year ended december 31 , 2019 compared to $ 336.6 million for the year ended december 31 , 2018. the increase in asset-based fees was primarily driven by an increase in revenues from exchange traded futures and options contracts linked to msci indexes . the increase in revenues from futures and options contracts was driven by approximately $ 5.0 million in additional fees associated with prior periods attributed to a retrospective price increase from a renegotiated contract entered into during the year ended december 31 , 2019 , as well as the cumulative impact of price and volume increases . the increase in revenues from asset-based fees was also driven by higher revenues from etfs linked to msci indexes , which was driven by a 7 . 6 % increase in average aum , partially offset by the impact of a change in product mix . in addition , the increase in revenues from asset-based fees was driven by higher revenues from non-etf passive products linked to msci indexes . the impact of foreign currency exchange rate fluctuations on revenues from asset-based fees was negligible . index segment adjusted ebitda expenses increased 10.2 % to $ 250.7 million for the year ended december 31 , 2019 compared to $ 227.6 million for the year ended december 31 , 2018 , reflecting higher expenses

