It doesn't seem like this chart takes inflation of the $ into account either, making it irrelevant over time. $1.25 was a lot more valuable even 30 years ago than it is today.
"And making sure everyone's making at least $1.25 a day isn't the end of the fight either. The world's median income is still only $3 to $4 a day. By comparison, the poverty line in the US for a family of four is $16.61 per person per day. Once under-$1.25-a-day poverty is eradicated, the world needs to set about eradicating under-$15-a-day poverty, which will be a substantially harder task."