The population increased from ~700million to ~1 billion over that time frame. An 8% increase in the number of people living in poverty while the population grew 42% is still progress. The US has a similar history economic growth lifted most poeple out of poverty, but it took wealth redistribution to reduce the number of people living in abject poverty. (Now we have beggars making 20 times what an Indian day labor makes, but 100 years ago things where vary different.)

PS: The simple poverty numbers say vary little. If a farmer in the third world with a wife and and five kids he is unlikely to get out of poverty any time soon. But, with a reasonable education his kids can lead a much better life.