Consider the following asset values and Basel III standardised credit risk weights for Fourth Bank: $100 million in assets in the 0 percent risk-weight category, $200 million in assets in the 20 percent risk-weight category, $500 million in assets in the 50 percent risk-weight category, and $750 million in assets in the 100 percent risk-weight category. The bank does not have any off-balance-sheet business.

Fourth Bank has $57 million in Tier 1 capital. What is this bank's Tier 1 risk-based capital ratio (assuming there is no market risk or operational risk)?