The inflation report that's closely watched by the Federal Reserve — the Personal Consumption Expenditure price index — was published on May 31 for April data and sparked a fresh market rally in June, pushing major indexes to their all-time highs.

As traders brace for Friday's PCE price index report for May, scheduled for release at 8:30 a.m. ET, many are wondering whether new favorable inflation data could bring the bulls back to Wall Street after some mixed performance in recent sessions.

May's PCE Report: What Do Economists Expect?

The PCE price index is expected to decrease from 2.7% year...