BBC News By Stephen Fairclough image captionUniversal basic incomes gives a regular sum to everyone, regardless of their income Supporters of universal basic income have called for a trial in Wales to include everyone living in a test area. UBI pays everyone a fixed sum, regardless of their circumstances. The Welsh government has said its small trial could involve people leaving the care system. In an open letter to the first minister, signatories, including the future generations commissioner, said it needed to cover geographical areas for it to be an effective test. Trials have taken place in Finland and California, with a 12-year project running in Kenya.