The World Bank's Facebook page features a chart from "Weekly EdStat" on "Which countries have improved their adult literacy rates the most over time?":
The chart shows some significant increases in some countries. Not sure if the report on which it was based has any treatment of multilingual literacy. All of the top ten speak several languages, so the topic seems very important.
I append my comments to that page below:
Nice chart and good news. Would be interested to see the write up. One unfortunate gap I've noted (without having studied it in depth) is the lack of attention to the question of "which languages?" in multilingual countries such as all of those in your list. The question has several dimensions from who is counted as literate (for instance does someone in Niger who can read Hausa in Arabic script but not French considered literate?) to implications for policy (teaching only in one language?). To a certain degree, literacy skills are transferable - the associating of symbols with sounds and meaning - but experience in Africa also shows that schooling children only in a second language like English or French does not mean that they can then simply read and write their first languages or other tongues used in their society. Ethnologue frequently gives literacy figures for language communities as "L1" and "L2" (first & second languages); other studies could follow that and go further to develop metrics that show more dimensions than a single % figure can show, and important implications in multilingual societies. At the beginning of the UN Literacy Decade, I began an email list on "multilingual literacy" to explore this issue, but it needs a more systematic advocacy and agenda.