The social rates of return to R&D vary. For the UK they are estimated at over 80 per cent. for manufacturing and 30 per cent. for public R&D in pharmaceuticals. Just under 200 new university spin-off firms were set up in 2002–03 compared to 70 a year on average from 1994–99. Over the past two years, 20 university spin out companies have floated on the stock market with a combined market value of over £1 billion.