February footfall saw a 2.3% drop compared to 12 months earlier; Scotland and Northern Ireland saw an increase of 1.2% and 1.3% respectively. The UK average saw a 0.8% drop.
Greater London and Wales saw the biggest decline.
Sara Jones from the Welsh Retail Consortium said the figures will be of "continued concern for retailers".
Despite a twelfth successive month of falling shoppers, there was some recovery from the January slump.
Diane Wehrle, of Springboard, which compiled the data, said the Welsh figures "must be put into the context of a much greater drop of 8.8% in February last year and 4.6% fall in January".
Ms Jones said the WRC will work with partners, including the Welsh government, to look at how regeneration strategies can help boost shopper numbers.
Wales has seen the largest drop in the number of shoppers in UK nations and regions, according to new figures.