the federal funds rate has been at a range of zero to 0.25 % since december 2008. our combined funds held for clients and corporate investment portfolios earned an average rate of return of 1.1 % for fiscal 2012 , compared to 1.3 % for fiscal 2011 and 1.5 % for fiscal 2010. highlights of our financial results for fiscal 2012 compared to fiscal 2011 are as follows : payroll service revenue increased 5 % to $ 1.5 billion . human resource services revenue increased 13 % to $ 676.2 million . interest on funds held for clients decreased 9 % to $ 43.6 million . total revenue increased 7 % to $ 2.2 billion . operating income increased 9 % to $ 853.9 million , and operating income , net of certain items , increased 10 % to $ 810.3 million . refer to the non-gaap financial measure discussion on the following page for further information on operating income , net of certain items . net income and diluted earnings per share each increased 6 % to $ 548.0 million and $ 1.51 per share , respectively . dividends of $ 460.5 million were paid to stockholders , representing 84 % of net income . our results for fiscal 2012 benefited from the inclusion of surepayroll , inc. ( surepayroll ) , a provider of payroll processing for small businesses , acquired on february 8 , 2011 , and eplan services , inc. ( eplan ) , a provider of recordkeeping and administrative solutions to the defined contribution marketplace , acquired on may 3 , 2011. these acquisitions in fiscal 2011 and an immaterial business acquisition in fiscal 2012 contributed approximately 2 % in total revenue growth for fiscal 2012 . 14 non-gaap financial measure in addition to reporting operating income , a united states ( u.s. ) generally accepted accounting principle ( gaap ) measure , we present operating income , net of certain items , which is a non-gaap measure . we believe operating income , net of certain items , is an appropriate additional measure , as it is an indicator of our core business operations performance period over period . it is also the basis of the measure used internally for establishing the following year 's targets and measuring management 's performance in connection with certain performance-based compensation payments and awards . operating income , net of certain items , excludes interest on funds held for clients and the expense charge in fiscal 2010 to increase the litigation reserve . interest on funds held for clients is an adjustment to operating income due to the volatility of interest rates , which are not within the control of management . the expense charge to increase the litigation reserve is also an adjustment to operating income due to its unusual and infrequent nature . it is outside the normal course of our operations and obscures the comparability of performance period over period . operating income , net of certain items , is not calculated through the application of gaap and is not the required form of disclosure by the securities and exchange commission . as such , it should not be considered as a substitute for the gaap measure of operating income and , therefore , should not be used in isolation , but in conjunction with the gaap measure . the use of any non-gaap measure may produce results that vary from the gaap measure and may not be comparable to a similarly defined non-gaap measure used by other companies . business outlook our client base totaled approximately 567,000 clients as of may 31 , 2012 , compared to approximately 564,000 clients as of may 31 , 2011 , and approximately 536,000 clients as of may 31 , 2010. our client base increased 0.5 % for fiscal 2012 , compared to an increase of 5.2 % for fiscal 2011 and a decline of 3.2 % for fiscal 2010. our organic client base growth was essentially flat for fiscal 2012 and declined 0.9 % for fiscal 2011. for fiscal 2012 , payroll services client retention was approximately 80 % of our beginning client base , a return to historical levels . this is a slight increase over fiscal 2011. through our focus on providing high-quality service to our customers to maximize client retention , we received the highest client satisfaction results in our history . our ancillary services provide services to employers and employees beyond payroll , but effectively leverage payroll processing data and , therefore , are beneficial to our operating margin . the following statistics demonstrate the growth in our human resource services ancillary service offerings : replace_table_token_5_th ( 1 ) growth rates exclude impact of acquisition of eplan . ( 2 ) includes paychex hr essentials as of may 31 , 2012 and 2011 . ( 3 ) includes workers ' compensation insurance services clients and health and benefits services clients . continued investment in our business is critical to our success . we continued to expand our product portfolio , through internal development and acquisitions , to add value for our clients . in the second half of fiscal 2011 , we acquired surepayroll and eplan . these acquisitions have created excellent opportunities in their markets , and allow paychex to offer a full range of payroll and 401 ( k ) outsourcing alternatives . during fiscal 2012 , we continued to integrate these acquired companies . in december 2011 , we purchased icon time systems , inc. , a provider of time and attendance solutions for small and medium-sized businesses , with whom we previously had a successful business relationship through one of our time and attendance offerings . additionally , 15 we launched new ancillary products in fiscal 2012. our business insurance payment service relieves business owners of the administrative burden of paying their insurance premiums . story_separator_special_tag million are excluded from the table above because the timing of actual payments can not be specifically or reasonably determined due to the variability in assumptions required to project the timing of future payments . advantage payroll services inc. ( advantage ) has license agreements with independently owned associate offices ( associates ) , which are responsible for selling and marketing advantage payroll services and performing certain operational functions , while paychex and advantage provide all centralized back-office payroll processing and payroll tax administration services . under these arrangements , advantage pays the associates commissions based on processing activity for the related clients . when we acquired advantage , there were fifteen associates . over the past few years , arrangements with some associates have been discontinued , and there are currently fewer than ten associates . since the actual amounts of future payments are uncertain , obligations under these arrangements are not included in the table above . commission expense for the associates for fiscal years 2012 , 2011 , and 2010 was $ 11.7 million , $ 10.4 million , and $ 9.9 million , respectively . in the normal course of business , we make representations and warranties that guarantee the performance of services under service arrangements with clients . historically , there have been no material losses related to such guarantees . in addition , we have entered into indemnification agreements with our officers and directors , which require us to defend and , if necessary , indemnify these individuals for certain pending or future legal claims as they relate to their services provided to us . we currently self-insure the deductible portion of various insured exposures under certain employee benefit plans . our estimated loss exposure under these insurance arrangements is recorded in other current liabilities on our consolidated balance sheets . historically , the amounts accrued have not been material . we also maintain insurance coverage in addition to our purchased primary insurance policies for gap coverage for employment practices liability , errors and omissions , warranty liability , theft and embezzlement , and acts of terrorism ; and capacity for deductibles and self-insured retentions through our captive insurance company . 23 off-balance sheet arrangements as part of our ongoing business , we do not participate in transactions with unconsolidated entities which would have been established for the purpose of facilitating off-balance sheet arrangements or other limited purposes . we do maintain investments as a limited partner in low-income housing projects that are not considered part of our ongoing operations . these investments are accounted for under the equity method of accounting and are less than 1 % of our total assets as of may 31 , 2012. operating cash flow activities replace_table_token_15_th the decrease in our operating cash flows for fiscal 2012 resulted mainly from fluctuations in operating assets and liabilities , partially offset by higher net income adjusted for non-cash items . the increase in our operating cash flows for fiscal 2011 resulted mainly from increases in net income and fluctuations in operating assets and liabilities . the fluctuations in our operating assets and liabilities between periods for both fiscal 2012 and fiscal 2011 were primarily related to the timing of collections from clients and payments for compensation , peo payroll , income tax , and other liabilities . investing cash flow activities replace_table_token_16_th funds held for clients and corporate investments : funds held for clients consist of short-term funds and available-for-sale securities . corporate investments are primarily comprised of available-for-sale securities . the portfolio of funds held for clients and corporate investments is detailed in note e of the notes to consolidated financial statements , contained in item 8 of this form 10-k. the fluctuation in the net change in funds held for clients and corporate investment activities for fiscal 2012 as compared to fiscal 2011 is largely due to timing within the client funds portfolio , as there was a large inflow of collections on may 31 , 2012 that was invested primarily in short-term investments on that date . see further discussion of this timing in the financing cash flows discussion of net change in client fund obligations . in addition , we increased our investment in longer-term available-for-sale securities within our corporate portfolio in fiscal 2012. the fluctuation in the net change in funds held for clients and corporate investment activities for fiscal 2011 as compared to fiscal 2010 was related to the mix of investment securities . in fiscal 2011 , we continued to increase our investment in vrdns and the amounts of purchases and sales for available-for-sale securities increased . however , partially offsetting this impact was the related liquidation of cash equivalents and the impact on cash equivalents from timing of remittances within the funds held for clients ' portfolio as compared to collections surrounding the fiscal year-end . see further discussion of this timing in the financing cash flows discussion of net change in client fund obligations . 24 in general , fluctuations in net funds held for clients and corporate investment activities primarily relate to timing of purchases , sales , or maturities of investments . the amount of funds held for clients will vary based upon the timing of collection of client funds , and the related remittance of funds to applicable tax or regulatory agencies for payroll tax administration services and to employees of clients utilizing employee payment services . additional discussion of interest rates and related risks is included in the market risk factors section , contained in item 7a of this form 10-k. purchases of long-lived assets : to support our continued client and ancillary product growth , purchases of property and equipment were made for data processing equipment and software , and for the expansion and upgrade of various operating facilities . during fiscal years 2012 , 2011 , and 2010 , we purchased approximately $ 2.6 million , $ 5.7 million , and $ 3.2 million ,

financial position and liquidity the supply of high credit quality securities has been limited with the continued volatility in the global financial markets , thereby limiting our investment choices . despite this macroeconomic environment , our financial position as of may 31 , 2012 remained strong with cash and total corporate investments of $ 790.0 million and no debt . our investment strategy focuses on protecting principal and optimizing liquidity . yields on high quality financial instruments remain low , negatively impacting our income earned on funds held for clients and corporate investments . we invest predominately in municipal bonds  general obligation bonds ; pre-refunded bonds , which are secured by a u.s. government escrow ; and essential services revenue bonds . during fiscal 2012 , our primary short-term investment vehicles were high quality variable rate demand notes ( vrdns ) and federal deposit insurance corporation ( fdic ) insured deposit accounts . a substantial portion of our portfolios is invested in high credit quality securities with aaa and aa ratings and a-1/p-1 ratings on short-term securities . we limit the amounts that can be invested in any single issuer and invest in short- to intermediate-term instruments whose fair value is less sensitive to interest rate changes . we believe that our investments as of may 31 , 2012 were not other-than-temporarily impaired , nor has any event occurred subsequent to that date that would indicate any other-than-temporary impairment . our primary source of cash is our ongoing operations . cash flow from operations was $ 706.6 million for fiscal 2012. historically , we have funded our operations , capital purchases , business acquisitions , and dividend payments from our operating activities . our positive cash flows in fiscal 2012 allowed us to support our business growth and to pay substantial dividends to our stockholders . during fiscal 2012 , dividends paid to stockholders were 84 % of net income .


 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.
     ```financial position and liquidity the supply of high credit quality securities has been limited with the continued volatility in the global financial markets , thereby limiting our investment choices . despite this macroeconomic environment , our financial position as of may 31 , 2012 remained strong with cash and total corporate investments of $ 790.0 million and no debt . our investment strategy focuses on protecting principal and optimizing liquidity . yields on high quality financial instruments remain low , negatively impacting our income earned on funds held for clients and corporate investments . we invest predominately in municipal bonds  general obligation bonds ; pre-refunded bonds , which are secured by a u.s. government escrow ; and essential services revenue bonds . during fiscal 2012 , our primary short-term investment vehicles were high quality variable rate demand notes ( vrdns ) and federal deposit insurance corporation ( fdic ) insured deposit accounts . a substantial portion of our portfolios is invested in high credit quality securities with aaa and aa ratings and a-1/p-1 ratings on short-term securities . we limit the amounts that can be invested in any single issuer and invest in short- to intermediate-term instruments whose fair value is less sensitive to interest rate changes . we believe that our investments as of may 31 , 2012 were not other-than-temporarily impaired , nor has any event occurred subsequent to that date that would indicate any other-than-temporary impairment . our primary source of cash is our ongoing operations . cash flow from operations was $ 706.6 million for fiscal 2012. historically , we have funded our operations , capital purchases , business acquisitions , and dividend payments from our operating activities . our positive cash flows in fiscal 2012 allowed us to support our business growth and to pay substantial dividends to our stockholders . during fiscal 2012 , dividends paid to stockholders were 84 % of net income .
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 Suspicious Activity Report : the federal funds rate has been at a range of zero to 0.25 % since december 2008. our combined funds held for clients and corporate investment portfolios earned an average rate of return of 1.1 % for fiscal 2012 , compared to 1.3 % for fiscal 2011 and 1.5 % for fiscal 2010. highlights of our financial results for fiscal 2012 compared to fiscal 2011 are as follows : payroll service revenue increased 5 % to $ 1.5 billion . human resource services revenue increased 13 % to $ 676.2 million . interest on funds held for clients decreased 9 % to $ 43.6 million . total revenue increased 7 % to $ 2.2 billion . operating income increased 9 % to $ 853.9 million , and operating income , net of certain items , increased 10 % to $ 810.3 million . refer to the non-gaap financial measure discussion on the following page for further information on operating income , net of certain items . net income and diluted earnings per share each increased 6 % to $ 548.0 million and $ 1.51 per share , respectively . dividends of $ 460.5 million were paid to stockholders , representing 84 % of net income . our results for fiscal 2012 benefited from the inclusion of surepayroll , inc. ( surepayroll ) , a provider of payroll processing for small businesses , acquired on february 8 , 2011 , and eplan services , inc. ( eplan ) , a provider of recordkeeping and administrative solutions to the defined contribution marketplace , acquired on may 3 , 2011. these acquisitions in fiscal 2011 and an immaterial business acquisition in fiscal 2012 contributed approximately 2 % in total revenue growth for fiscal 2012 . 14 non-gaap financial measure in addition to reporting operating income , a united states ( u.s. ) generally accepted accounting principle ( gaap ) measure , we present operating income , net of certain items , which is a non-gaap measure . we believe operating income , net of certain items , is an appropriate additional measure , as it is an indicator of our core business operations performance period over period . it is also the basis of the measure used internally for establishing the following year 's targets and measuring management 's performance in connection with certain performance-based compensation payments and awards . operating income , net of certain items , excludes interest on funds held for clients and the expense charge in fiscal 2010 to increase the litigation reserve . interest on funds held for clients is an adjustment to operating income due to the volatility of interest rates , which are not within the control of management . the expense charge to increase the litigation reserve is also an adjustment to operating income due to its unusual and infrequent nature . it is outside the normal course of our operations and obscures the comparability of performance period over period . operating income , net of certain items , is not calculated through the application of gaap and is not the required form of disclosure by the securities and exchange commission . as such , it should not be considered as a substitute for the gaap measure of operating income and , therefore , should not be used in isolation , but in conjunction with the gaap measure . the use of any non-gaap measure may produce results that vary from the gaap measure and may not be comparable to a similarly defined non-gaap measure used by other companies . business outlook our client base totaled approximately 567,000 clients as of may 31 , 2012 , compared to approximately 564,000 clients as of may 31 , 2011 , and approximately 536,000 clients as of may 31 , 2010. our client base increased 0.5 % for fiscal 2012 , compared to an increase of 5.2 % for fiscal 2011 and a decline of 3.2 % for fiscal 2010. our organic client base growth was essentially flat for fiscal 2012 and declined 0.9 % for fiscal 2011. for fiscal 2012 , payroll services client retention was approximately 80 % of our beginning client base , a return to historical levels . this is a slight increase over fiscal 2011. through our focus on providing high-quality service to our customers to maximize client retention , we received the highest client satisfaction results in our history . our ancillary services provide services to employers and employees beyond payroll , but effectively leverage payroll processing data and , therefore , are beneficial to our operating margin . the following statistics demonstrate the growth in our human resource services ancillary service offerings : replace_table_token_5_th ( 1 ) growth rates exclude impact of acquisition of eplan . ( 2 ) includes paychex hr essentials as of may 31 , 2012 and 2011 . ( 3 ) includes workers ' compensation insurance services clients and health and benefits services clients . continued investment in our business is critical to our success . we continued to expand our product portfolio , through internal development and acquisitions , to add value for our clients . in the second half of fiscal 2011 , we acquired surepayroll and eplan . these acquisitions have created excellent opportunities in their markets , and allow paychex to offer a full range of payroll and 401 ( k ) outsourcing alternatives . during fiscal 2012 , we continued to integrate these acquired companies . in december 2011 , we purchased icon time systems , inc. , a provider of time and attendance solutions for small and medium-sized businesses , with whom we previously had a successful business relationship through one of our time and attendance offerings . additionally , 15 we launched new ancillary products in fiscal 2012. our business insurance payment service relieves business owners of the administrative burden of paying their insurance premiums . story_separator_special_tag million are excluded from the table above because the timing of actual payments can not be specifically or reasonably determined due to the variability in assumptions required to project the timing of future payments . advantage payroll services inc. ( advantage ) has license agreements with independently owned associate offices ( associates ) , which are responsible for selling and marketing advantage payroll services and performing certain operational functions , while paychex and advantage provide all centralized back-office payroll processing and payroll tax administration services . under these arrangements , advantage pays the associates commissions based on processing activity for the related clients . when we acquired advantage , there were fifteen associates . over the past few years , arrangements with some associates have been discontinued , and there are currently fewer than ten associates . since the actual amounts of future payments are uncertain , obligations under these arrangements are not included in the table above . commission expense for the associates for fiscal years 2012 , 2011 , and 2010 was $ 11.7 million , $ 10.4 million , and $ 9.9 million , respectively . in the normal course of business , we make representations and warranties that guarantee the performance of services under service arrangements with clients . historically , there have been no material losses related to such guarantees . in addition , we have entered into indemnification agreements with our officers and directors , which require us to defend and , if necessary , indemnify these individuals for certain pending or future legal claims as they relate to their services provided to us . we currently self-insure the deductible portion of various insured exposures under certain employee benefit plans . our estimated loss exposure under these insurance arrangements is recorded in other current liabilities on our consolidated balance sheets . historically , the amounts accrued have not been material . we also maintain insurance coverage in addition to our purchased primary insurance policies for gap coverage for employment practices liability , errors and omissions , warranty liability , theft and embezzlement , and acts of terrorism ; and capacity for deductibles and self-insured retentions through our captive insurance company . 23 off-balance sheet arrangements as part of our ongoing business , we do not participate in transactions with unconsolidated entities which would have been established for the purpose of facilitating off-balance sheet arrangements or other limited purposes . we do maintain investments as a limited partner in low-income housing projects that are not considered part of our ongoing operations . these investments are accounted for under the equity method of accounting and are less than 1 % of our total assets as of may 31 , 2012. operating cash flow activities replace_table_token_15_th the decrease in our operating cash flows for fiscal 2012 resulted mainly from fluctuations in operating assets and liabilities , partially offset by higher net income adjusted for non-cash items . the increase in our operating cash flows for fiscal 2011 resulted mainly from increases in net income and fluctuations in operating assets and liabilities . the fluctuations in our operating assets and liabilities between periods for both fiscal 2012 and fiscal 2011 were primarily related to the timing of collections from clients and payments for compensation , peo payroll , income tax , and other liabilities . investing cash flow activities replace_table_token_16_th funds held for clients and corporate investments : funds held for clients consist of short-term funds and available-for-sale securities . corporate investments are primarily comprised of available-for-sale securities . the portfolio of funds held for clients and corporate investments is detailed in note e of the notes to consolidated financial statements , contained in item 8 of this form 10-k. the fluctuation in the net change in funds held for clients and corporate investment activities for fiscal 2012 as compared to fiscal 2011 is largely due to timing within the client funds portfolio , as there was a large inflow of collections on may 31 , 2012 that was invested primarily in short-term investments on that date . see further discussion of this timing in the financing cash flows discussion of net change in client fund obligations . in addition , we increased our investment in longer-term available-for-sale securities within our corporate portfolio in fiscal 2012. the fluctuation in the net change in funds held for clients and corporate investment activities for fiscal 2011 as compared to fiscal 2010 was related to the mix of investment securities . in fiscal 2011 , we continued to increase our investment in vrdns and the amounts of purchases and sales for available-for-sale securities increased . however , partially offsetting this impact was the related liquidation of cash equivalents and the impact on cash equivalents from timing of remittances within the funds held for clients ' portfolio as compared to collections surrounding the fiscal year-end . see further discussion of this timing in the financing cash flows discussion of net change in client fund obligations . 24 in general , fluctuations in net funds held for clients and corporate investment activities primarily relate to timing of purchases , sales , or maturities of investments . the amount of funds held for clients will vary based upon the timing of collection of client funds , and the related remittance of funds to applicable tax or regulatory agencies for payroll tax administration services and to employees of clients utilizing employee payment services . additional discussion of interest rates and related risks is included in the market risk factors section , contained in item 7a of this form 10-k. purchases of long-lived assets : to support our continued client and ancillary product growth , purchases of property and equipment were made for data processing equipment and software , and for the expansion and upgrade of various operating facilities . during fiscal years 2012 , 2011 , and 2010 , we purchased approximately $ 2.6 million , $ 5.7 million , and $ 3.2 million ,

