The Economist Intelligence Unit has put together a report for Capgemini on Big Data, its usage, factors effecting decision making according to which almost around 26% of perceived improvement in performance through big data initiative in last 3 years while 41% is expected for next 3 years.
While that is substantial improvement the report highlights there are still issues in terms of buy-in from senior management and skills required to analyze the data at hand and how effective the anlysis will be to make a validated improvement.
Here is an infographic from Capgemini that provides all such data.




