The WACC of Prothena Corporation PLC (PRTA) is 7.0%.
| Range | Selected | |
| Cost of equity | 7.30% - 11.20% | 9.25% |
| Tax rate | 4.30% - 6.90% | 5.60% |
| Cost of debt | 5.00% - 5.00% | 5.00% |
| WACC | 6.1% - 8.0% | 7.0% |
| Category | Low | High |
| Long-term bond rate | 3.9% | 4.4% |
| Equity market risk premium | 4.6% | 5.6% |
| Adjusted beta | 0.75 | 1.14 |
| Additional risk adjustments | 0.0% | 0.5% |
| Cost of equity | 7.30% | 11.20% |
| Tax rate | 4.30% | 6.90% |
| Debt/Equity ratio | 1 | 1 |
| Cost of debt | 5.00% | 5.00% |
| After-tax WACC | 6.1% | 8.0% |
| Selected WACC | 7.0% | |