EY has done researches about changes of work and have published their findings about growth of contingent workforce globally.
Key insights by EY:
Fifty-six percent of organizations report that the most significant reason for using contingent workers is to complete projects where the specific expertise is beyond the capability of the exisiting workforce.
Organizations also see contingent workers as helping to control labor costs (55%)
More than two in five (42%) of organizations use contingent workers to respond to seasonal workforce requirements
You may find their findings: https://gigeconomy.ey.com/