Operating Income Morningstar, Inc. 2010 Annual Report 83 Revenue from our other investment research products was essen- tially flat in 2010 after declining in 2009. In 2010, higher revenue  from conferences and corporate credit ratings research helped off- set the continuing decline in revenue from newsletters and books.  In the first quarter of 2009, we discontinued three of the print pub- lications we previously published in the first quarter of each year:  Morningstar Funds 500 ,  Morningstar Stocks 500 , and  Morningstar  ETFs 150 . Lower advertising revenue from publications sold in  Australia and lower revenue from the annual Morningstar Investment  Conference held in the second quarter also contributed to the decline  in 2009. Operating expense decreased $3.8 million in 2009 as cost reductions  for bonuses, other compensation expense, and advertising and  marketing were partially offset by additional operating expense  from acquisitions. Bonus expense declined $11.0 million in 2009.  Most of this reduction reflects the changes we made to our bonus  program for 2009 as part of our efforts to better align our cost  structure with revenue. The reduction in bonus expense also reflects  a slowdown in our financial performance in 2009 compared with 2008. Other compensation-related expense was down, primarily because we suspended matching contributions to our 401(k)  plan in the United States, reducing operating expense by $4.3 million  in 2009. Investment research revenue declined in 2010 as well as in 2009.  As mentioned above, the period covered by GARS expired at the end  of July 2009. Our post-settlement equity research revenue in 2010  replaced approximately one-third of the annual GARS revenue. GARS  revenue was $12.5 million in 2009, compared with $21.9 million in  2008. We entered into new equity research contracts with two of  the banks that were clients under GARS. In addition, we’re continu- ing to provide broad equity coverage to individual investors, finan- cial advisors, and institutions through a variety of other channels. Licensed Data made positive contributions to segment revenue in  both 2010 and 2009, reflecting strong renewal rates and new client  contracts. The Licensed Data service gives institutions access to a  full range of proprietary investment data spanning numerous invest- ment databases, including real-time pricing data. The data packages  we offer include proprietary statistics, such as the Morningstar  Style Box and Morningstar Rating, and a wide range of other data,  including information on investment performance, risk, portfolios,  operations data, fees and expenses, cash flows, and ownership. Operating margin for the Investment Information segment declined  7.1 percentage points in 2010. Approximately 6.4 percentage points  of the margin decline reflects higher compensation-related expense  as a percentage of revenue. Acquisitions had a slightly negative  impact on the margin. In 2009, operating income for the Investment Information segment  was $138.4 million, a slight decrease compared with 2008, as the $4.1 million decline in revenue was partially offset by lower  operating expense. The number of U.S. licenses for Morningstar Advisor Workstation  increased slightly to 153,170 as of December 31, 2010 from 148,392  as of December 31, 2009 and 151,874 as of December 31, 2008.  Principia subscriptions totaled 32,681as of December 31, 2010, down  from 35,844 as of December 31, 2009 and 43,019 as of December  31, 2008. Operating expense was up $69.0 million in 2010, with additional  costs from acquisitions contributing approximately 45% of the  increase. Higher salaries (reflecting expanded headcount) and incen- tive compensation (including bonus and sales commission expense)  also contributed to the increase. Bonus expense increased $10.9  million in 2010, including incremental bonus expense from recent  acquisitions. An increase in employee benefits expense, including  employee healthcare benefits and the partial reinstatement of match- ing contributions to our 401(k) plan in the United States, also con- tributed to the increase, but to a lesser extent. In 2010, operating income for the Investment Information segment  decreased $10.7 million, or 7.7%, as operating expense increased  more than revenue. Advisor software revenue represented approximately 25.9% of the  increase in segment revenue in 2010 as higher revenue from Advisor  Workstation and Site Builder and Licensed Tools offset the decline  in Principia revenue. In comparison, advisor software revenue was  down in 2009 because lower Principia revenue more than offset the  increase in Advisor Workstation and other products. Principia rev- enue declined 6.6% in 2010 and 14.3% in 2009. The decline partly  reflects clients migrating from Principia to Advisor Workstation.