Dr. Thomas Conefrey:

On illegal activities, the CSO adopted international standards, as of its 2013 national accounts, and they now incorporate estimates of illegal activities but also research and development. While the illegal activities have got a lot of media attention, they are by far the smallest component of the upward revision to GDP. It has increased the level of GDP. The CSO has revised it back but it does not affect annual growth rates, it just lifts the level again. By far the largest component of the change is due to the inclusion of research and development expenditures in GDP rather than illegal activities.