| Mean | Range | ||
| Mean employment duration (years) | 3.1 | <0.01–62.0 | |
| Mean exposure duration (years) | 2.2 | 0–33.5 | |
| Mean length of follow-up (years) | 12.8 | 0–45.0 | |
| Mean styrene exposure (ppm) | 63.1 | 0–205.0 | |
| Mean cumulative styrene exposure (ppm-years) | 158.0 | 0–4543.1 | |
*Per cents may not add to 100 because of rounding.