VAT was only 15% last year, and the exchange rate was around $1.65 to £1 as opposed to around $1.49 currently.
So adjusting for exchange rate and inflation the drive was around $2.55 / GB and now it is $3.05/GB , a 19% rise.
NAND prices were at a low in summer of last year due to the recession, but resurging demand from Smartphones and SSD's pushed prices up by around 23% where it has been stable for the past 6 months.
Considering a 23% rise in NAND costs, a 19% rise in the base price of the SSD is actually not that bad.
Prices will start falling eventually, the main obstacle is the amount of time it takes suppliers to build a new NAND facility. Toshiba has a big new facility coming online next year.