Staffing Industry Analysts estimates global spend on contingent labor was $2.5 trillion in 2012. Our estimate is based on the definition of contingent work as listed in our our Global Contingent Workforce Lexicon (PDF). Independent contractors outpaced all other CW categories, at $1.5 trillion. This estimate also includes $736 billion for statement-of-work consultants and $344 billion for workers sourced through staffing firms.
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