During the first six months of 2024, the following main currencies relevant to our operations decreased in value against the U.S. dollar: Argentinian peso by 75%, Turkish lira by 37%, Russian ruble by 15%, Chilean peso by 14%, Japanese yen by 11%, Ukrainian hryvna by 6% and new Israeli shekel by 3% (all compared on a six-month average basis). The following main currencies relevant to our operations increased in value against the U.S. dollar: Polish zloty by 7%, Mexican peso by 6%, Swiss franc by 3% and the British pound by 3%.
As a result, exchange rate movements during the first six months of 2024, including hedging effects, negatively impacted overall revenues by $161 million and our operating income by $66 million, in comparison to the first six months of 2023.
In the first six months of 2024, a positive hedging impact of $10 million was recognized under revenues, and a negative hedging impact of $6 million was recognized under cost of sales. In the first six months of 2023, a negative hedging impact of $2 million was recognized under revenues and a minimal hedging impact was recognized under cost of sales.
Hedging transactions against future projected revenues and expenses are recognized on the balance sheet at their fair value on a quarterly basis, while the foreign exchange impact on the underlying revenues and expenses may occur in subsequent quarters. See note 8d to our consolidated financial statements.
2024 Aggregated Contractual Obligations
There have not been any material changes in our assessment of material contractual obligations and commitments as set forth in Item 7 of our Annual Report on Form 10-K for the year ended December 31, 2023.
Liquidity and Capital Resources
Total balance sheet assets were $41,338 million as of June 30, 2024, compared to $43,479 million as of December 31, 2023.
Our working capital balance, which includes accounts receivables net of SR&A, inventories, prepaid expenses and other current assets, accounts payables, employee-related obligations, accrued expenses and other current liabilities, was negative $1,283 million as of June 30, 2024, compared to negative $1,374 million as of December 31, 2023. This increase was mainly due to a decrease in accounts payables, driven mainly by timing of inventory purchase pattern, an increase in accounts receivables, net of SR&A, driven mainly from higher sales during the second quarter of 2024 with extended payment terms into the third quarter, and a decrease in employee-related obligations mainly due to performance incentive payments to employees for 2023, partially offset by a classification of working capital balance related to our business venture in Japan as held for sale, as well as an increase in other current liabilities and a decrease in prepaid expenses.
Employee-related obligations, as of June 30, 2024 were $492 million, compared to $611 million as of December 31, 2023. The decrease in the first six months of 2024 was mainly due to performance incentive payments to employees for 2023, partially offset by an accrual for performance incentive payments to employees for 2024.
Cash investment in property, plant and equipment in the second quarter of 2024 was $92 million, compared to $119 million in the second quarter of 2023. Depreciation in the second quarter of 2024 was $113 million, compared to $138 million in the second quarter of 2023.
Cash and cash equivalents as of June 30, 2024 were $2,258 million compared to $3,226 million as of December 31, 2023.
Our cash on hand that is not used for ongoing operations is generally invested in bank deposits as well as liquid securities that bear fixed and floating rates.
Teva’s principal sources of short-term liquidity are its cash on hand, existing cash investments, liquid securities and available credit facilities, primarily our $1.8 billion unsecured syndicated sustainability-linked revolving credit facility, entered into in April 2022, as amended in February 2023 and on May 3, 2024 (“RCF”). See note 7 to our consolidated financial statements.
Debt Balance and Movements
As of June 30, 2024, our debt was $18,640 million, compared to $19,833 million as of December 31, 2023. This decrease was mainly due to repayment at maturity of $956 million of 6% senior notes and a positive impact of $247 million from exchange rate fluctuations.
In April 2024, we repaid $956 million of our 6% senior notes at maturity.
As of June 30, 2024, our debt was effectively denominated in the following currencies: 59% in U.S. dollars, 39% in euros and 2% in Swiss francs.
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