Firm A has $1 billion in highly liquid assets. In a sudden stressed scenario, it estimates that retail customers will withdraw $150 million in deposits, and retail customers will be able to make $80 million of loan repayments. Firm A must deal with $60 million of margin and collateral calls on its derivatives transactions due to falling collateral values and greater volatility of the underlying assets. In addition, it has utilized $10 million of a total $100 million liquidity facility. What is the estimate of Firm A's stressed liquidity asset buffer?