update & statistical note: this figure is based only on those fed by Trussell Trust foodbanks. The Trussell Trust was set up in 1999 in Salisbury, and has grown to over 400 centres. There are other food banks (e.g. the Lords Larder here in Yeovil, which has been running since 1991. The 59,000 items they gave out to 3979 people in 2013 was a 25% rise on the year before, and 2014 is running ahead of 2013 in terms of demand. This isn't quite the exponential growth that the Trussell Trust have seen, but any growth is bad. The Feeding Britain report claims that there may be just as many independent food banks as those the Trussell Trust is running.
For example, in Somerset there is also the West Somerset Food Cupboard, though most of the others in the county (Bath, Taunton, Weston, Bridgwater, Somer Valley, Cheddar etc.) are supported by the TT.