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Mean total migration in millimetres (mm) over time
| 12 months (n = 137) | 24 months (n = 86) | 36 months (n = 108) | 48 months (n = 43) | |
|---|---|---|---|---|
| Migration of the trident PSL (mm/year) | 0.1 (0.0–1.7) | 0.4 (0.0–2.0) | 0.8 (0.0–1.1) | 1.5 (0.0–8.2) |
Range is given in brackets
