NEW YORK — In the face of persistent economic weakness, shoppers are purchasing store brands in growing numbers and overwhelmingly are satisfied with those purchases, according to data recently released by the Private Label Manufacturers Association.

A new P.L.M.A. report, “PLMA Consumer Research Report: Recession, Recovery and Store Brands” was published March 31.

More than 4 in 10 supermarket shoppers (43%) said they had recently shifted from a familiar national brand in favor of a private label alternative. By contrast, only 35% said they had made such a shift the last time the data were collected, in June 2009.

Results were based on a nationwide poll of nearly 800 main household grocery shoppers conducted for the P.L.M.A. by GfK Custom Research North America, based in New York.

Of shoppers who recently made the switch to store brands, 94% said the private label products compare favorably to previous choices in the same categories with only 6% unimpressed by the private label purchase.

Drilling further into this data, P.L.M.A. said 49% described their private label purchases “very favorably,” a major jump from June 2009 when only 26% of the purchases earned a very favorable rating.

The surveyed shoppers took a dim view of the economic picture, both from a current perspective and regarding the outlook.

Asked whether the economy had changed in recent months, 40% of those surveyed said conditions had deteriorated and 42% said they had stayed the same. Fewer than one in five shoppers thought the economic picture was improving.

As a result, 62% of those surveyed said they plan to buy more private label as they grapple with the tough economy.

The P.L.M.A. said 57% of shoppers say they purchase store brands frequently, up from 55% a year ago and the highest level ever.

“The new percentage is consistent across all age, regional and income demographics included in the study,” the P.L.M.A. said.