management 2019s discussion and analysis net interest income 2012 versus 2011 . net interest income on the consolidated statements of earnings was $ 3.88 billion for 2012 , 25% ( 25 % ) lower than 2011 . the decrease compared with 2011 was primarily due to lower average yields on financial instruments owned , at fair value , and collateralized agreements . 2011 versus 2010 . net interest income on the consolidated statements of earnings was $ 5.19 billion for 2011 , 6% ( 6 % ) lower than 2010 . the decrease compared with 2010 was primarily due to higher interest expense related to our long-term borrowings and higher dividend expense related to financial instruments sold , but not yet purchased , partially offset by an increase in interest income from higher yielding collateralized agreements . operating expenses our operating expenses are primarily influenced by compensation , headcount and levels of business activity . compensation and benefits includes salaries , discretionary compensation , amortization of equity awards and other items such as benefits . discretionary compensation is significantly impacted by , among other factors , the level of net revenues , overall financial performance , prevailing labor markets , business mix , the structure of our share-based compensation programs and the external environment . in the context of more difficult economic and financial conditions , the firm launched an initiative during the second quarter of 2011 to identify areas where we can operate more efficiently and reduce our operating expenses . during 2012 and 2011 , we announced targeted annual run rate compensation and non-compensation reductions of approximately $ 1.9 billion in aggregate . the table below presents our operating expenses and total staff. .
total staff at period-end 2 32400 33300 35700 1 . related revenues are included in 201cmarket making 201d on the consolidated statements of earnings . 2 . includes employees , consultants and temporary staff . 48 goldman sachs 2012 annual report .
Year Ended December
<i>$ in millions</i> 2012 2011 2010
Compensation and benefits $12,944 $12,223 $15,376
U.K. bank payrolltax — — 465
Brokerage, clearing, exchange anddistribution fees 2,208 2,463 2,281
Market development 509 640 530
Communications and technology 782 828 758
Depreciation and amortization 1,738 1,865 1,889
Occupancy 875 1,030 1,086
Professional fees 867 992 927
Insurance reserves<sup>1</sup> 598 529 398
Other expenses 2,435 2,072 2,559
Total non-compensation expenses 10,012 10,419 10,428
Total operating expenses $22,956 $22,642 $26,269
Total staff atperiod-end<sup>2</sup> 32,400 33,300 35,700
$ in millions year ended december 2012 year ended december 2011 year ended december 2010
compensation and benefits $ 12944 $ 12223 $ 15376
u.k . bank payrolltax 2014 2014 465
brokerage clearing exchange anddistribution fees 2208 2463 2281
market development 509 640 530
communications and technology 782 828 758
depreciation and amortization 1738 1865 1889
occupancy 875 1030 1086
professional fees 867 992 927
insurance reserves1 598 529 398
other expenses 2435 2072 2559
total non-compensation expenses 10012 10419 10428
total operating expenses $ 22956 $ 22642 $ 26269
total staff atperiod-end2 32400 33300 35700