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Barrier Secondary Collision Rates and 95% Confidence Intervals by Barrier Type, [NASS/CDS 1997–2008, inclusive]
| Barrier Type | Second Event | Weighted Percent | 95% CI on Percent |
|---|---|---|---|
| Concrete | No | 65.7 | 58.1 – 73.5 |
| Yes | 34.2 | 26.5 – 41.9 | |
| Metal | No | 66.5 | 58.0 – 75.0 |
| Yes | 33.5 | 25.0 – 42.0 |
