Ozone pollution caused significant damage to crops in the year 2000 and greater reductions in yields are predicted for 2030 for some regions of the world. In 2000, the global economic value of crop losses through surface ozone was estimated to be between US$14 and $26 billion, with 40 per cent of this cost occurring in China and India.
Source: The global impact of ozone on agricultural yields under current and future air quality legislation (2009). Van Dingenen, R., Dentener, F.J., Raes, F. et al. Atmospheric Environment. Doi:10.1016/j.atmosenv.2008.10.033.