The total assets of the exchange fund stood at $1.6454 trillion on April 30, $41.5 billion higher than March, the Monetary Authority says.

Foreign currency assets rose $34.5 billion and Hong Kong dollar assets grew by $7 billion.

The rise in foreign-currency assets was due mainly to purchases of foreign currencies with Hong Kong dollars and valuation gains on foreign-currency investments, while the rise in Hong Kong dollar assets was due to an increase in the balance of the banking system and valuation gains on Hong Kong equities held by the exchange fund.

These increases were partly offset by sales of Hong Kong dollars for foreign currencies.

The currency board account shows the monetary base at the end of April was $618.8 billion, an increase of $48.8 billion, or 8.6%, from the end of March. The rise was due mainly to increases in the aggregate balance and certificates of indebtedness.

The backing assets rose $46.3 billion, or 7.5%, to $662.9 billion. The increase was attributable mainly to an increase in the aggregate balance and the issuance of certificates of indebtedness in the monetary base together with interest from investments.

These increases were partly offset by revaluation losses, thus the backing ratio declined from 108.19% at the end of March to 107.13% at the end of April.