The GDP(ppp) per capita is the purchasing power parity value of all final goods and services produced within a country in a given year, divided by the average (mid year) population of the same year.
The definition above is straight from wiki and nothing to cry about.
Now here's the part that should make you weep tears of sorrow. If you have even half a brain.
In global rankings Zambia at no.138, is out- ranked by such God forsaken countries like Sudan, Libya, Iraq, Kosovo, Mauritania! Yes that's right, the same Mauritania where until today Black Africans are held as slaves by their Islamic masters.