Please answer the given financial question based on the context.
Context: management 2019s discussion and analysis net interest income 2013 versus 2012 . net interest income on the consolidated statements of earnings was $ 3.39 billion for 2013 , 13% ( 13 % ) lower than 2012 . the decrease compared with 2012 was primarily due to lower average yields on financial instruments owned , at fair value , partially offset by lower interest expense on financial instruments sold , but not yet purchased , at fair value and collateralized financings . 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 . see 201cstatistical disclosures 2014 distribution of assets , liabilities and shareholders 2019 equity 201d for further information about our sources of net interest income . 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 . the table below presents our operating expenses and total staff ( which includes employees , consultants and temporary staff ) . .
|$ in millions|year ended december 2013|year ended december 2012|year ended december 2011|
|compensation and benefits|$ 12613|$ 12944|$ 12223|
|brokerage clearing exchange anddistribution fees|2341|2208|2463|
|market development|541|509|640|
|communications and technology|776|782|828|
|depreciation and amortization|1322|1738|1865|
|occupancy|839|875|1030|
|professional fees|930|867|992|
|insurance reserves1|176|598|529|
|other expenses|2931|2435|2072|
|total non-compensation expenses|9856|10012|10419|
|total operating expenses|$ 22469|$ 22956|$ 22642|
|total staff at period-end|32900|32400|33300|
1 . related revenues are included in 201cmarket making 201d in the consolidated statements of earnings . goldman sachs 2013 annual report 45 .
Question: what is the percentage change in staff number in 2013?


Answer: The answer is:0.01543