U.K. CBI March retail sales survey index unexpectedly surged to +3 from -44, well above the Reuters median estimate for -40 and following an unexpected improvement to -25 in February. Meanwhile, the May expectations balance jumped to -15 from -42 for April. These were the highest readings since January 2008 and July 2008 respectively. CBI data is highly volatile and CBI today warned that the timing of Easter could be distorting the index. There has been anectotal evdience that Easter sales were relatively healthy but CBI today warned that the April figures should not be seen as an indication of highstreet revival.