JAKARTA, June 8 (Reuters) - Indonesia’s foreign exchange reserves dropped by $2.4 billion in May to $136.4 billion, central bank data showed on Tuesday, amid capital outflows linked to talks of potential policy tightening in developed economies. April’s $138.8 billion reserve level was Indonesia’s highest on record. The rupiah was volatile in May, strengthening rapidly in the first few days before weakening as much as 2%. (Reporting by Tabita Diela and Gayatri Suroyo; Editing by Himani Sarkar) Our Standards: The Thomson Reuters Trust Principles.