Dollar bulls are bewildered amid a sea of setbacks as investors ponder what's left of the rally that had pundits talking of dollar hegemony just months ago.

The U.S. currency slid Thursday toward the lowest closing level in almost four months against major peers after stagnant retail sales became the latest data to undermine prospects for Federal Reserve interest-rate increases. The greenback had climbed nine straight months through March with the first hike in almost a decade looming. The U.S. currency fell to its lowest level in almost three months against the euro.

“It is really all about dollar weakness across the board today as markets are still digesting the U.S. retail-sales data,” said Keng Goh, a foreign-exchange strategist at Royal Bank of Canada in London. While RBC expects the Fed to increase rates in September, “no doubt some of the weakness in the data will probably diminish that conviction a little bit.”