The total number of study participants and the year of the survey
| Regions | Year of survey | Total | |||
| 2000 | 2005 | 2011 | 2016 | ||
| Tigray | 1248 | 958 | 986 | 990 | 4182 |
| Afar | 715 | 574 | 942 | 1074 | 3305 |
| Amhara | 1770 | 1437 | 1035 | 938 | 5180 |
| Oromia | 2420 | 1897 | 1357 | 1547 | 7221 |
| Somali | 771 | 661 | 825 | 1513 | 3770 |
| Benishangul-Gumuz | 875 | 684 | 813 | 875 | 3247 |
| SNNP | 1759 | 1719 | 1274 | 1275 | 6027 |
| Gambela | 647 | 511 | 670 | 704 | 2532 |
| Hareri | 614 | 509 | 547 | 583 | 2253 |
| Addis Ababa | 542 | 381 | 329 | 430 | 1682 |
| Dire Dawa | 623 | 406 | 533 | 537 | 2099 |
| Total | 11 984 | 9737 | 9311 | 10 466 | 41 498 |
*South nation nationality and people’s region