| Variable | Cohort I (1993-1997) | Cohort II (1998-2003) | Cohort III (2004-2008) | Cohort IV (2009-2013) | p value |
| No. (%) | 515 (9.3) | 822 (14.8) | 2170 (39.0) | 2054 (36.9) | - |
| Number of sexual acts per week (Mean, SD) | 7.7 (5.0) | 7.5 (5.2) | 7.5 (5.2) | 6.1 (4.9) | <0.001 |
| Age at initiation of sex work (years) (Mean, SD) | 20.9 (5.2) | 20.8 (5.4) | 22.8 (5.6) | 24.5 (5.2) | <0.001 |
| Irregular partners (%)* | 36 (6.9) | 52 (6.3) | 283 (13.0) | 615 (29.9) | <0.001 |
| Alcohol use (%) | 229 (44.4) | 427 (51.9) | 1129 (52.0) | 749 (36.4) | <0.001 |
| Illiteracy (%) | 120 (23.3) | 167 (20.3) | 486 (22.4) | 505 (24.6) | 0.08 |
| Higher education (%) | 225 (43.7) | 374 (45.5) | 933 (43.0) | 765 (37.2) | <0.001 |
| Never employed (%) | 84 (16.3) | 188 (22.8) | 494 (22.8) | 404 (19.7) | 0.002 |