Tweets, trade and market volatility are failing to shake the U.S. investment-grade issuance market and borrowers are teeing up for another big round of debt sales this week. In high yield the turmoil has made buyers shy away and companies have shelved their issuance plans to post Labor Day, while the loan market anticipates a low-key week for new deals as the summer slowdown approaches.

While no jumbo offerings like last week’s $13 billion Occidental Petroleum Corp. bond sale are expected, dealers are projecting $30 billion to price. Investment-grade borrowers have sold about $41 billion so far this month, fueled by lower rates and a drop in new issue supply this year.

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