If there is any doubt that the global apparel trade has involved a massive scramble to the bottom when it comes to wages and working conditions, the Center for American Progress and the anti-sweatshop Workers Rights Consortium would like to dispel it. In a new study of textile industry wages in the world’s top garment exporters, new research concludes that on an inflation-adjusted basis, earnings for factory workers in most of the countries have been falling.

That includes Bangladesh, in the news recently because of deadly industrial accidents, but also Mexico, seen as a developing world success story. Measured on a real purchasing power parity basis – meaning wages were adjusted to account for the local cost of living – Bangladesh textile wages fell more than 2 percent from 2001 to 2011, while in Mexico they dropped nearly 30 percent.

An interesting exception: Textile industry wages in China rose 125 percent over the same time, pulled up by increasing wages overall in the country, and perhaps explaining why so much textile production is relocating to places like Bangladesh and Cambodia.

Overall, the research challenges one of the central assumptions in the debate about world garment industry conditions: namely that whatever else, textile shops provide a steady income for millions of the otherwise poor and unemployed. What this study suggests is that while the income may be steady, it may not be a living wage, and that even as textile production has boomed in some countries, the benefits have not filtered down.

Correction: An earlier version of this post had an incorrect byline.