The Fed started raising its key short-term rate in March last year, but investors more recently had become fixated on longer-dated market rates, which are driven by a variety of factors like economic growth and inflation expectations, not just the Fed’s policy decisions. These long-term rates began surging in August, intensifying concerns about the sustainability of the government’s $33 trillion debt pile, among other worries. Those concerns dissipated somewhat this week. Investors welcomed plans from the Treasury Department to skew its borrowing toward shorter-term debt, taking pressure off longer-dated yields. Then, Jerome H. Powell, the Fed chair, appeared to soothe investors’ nerves after the central bank held rates steady for a second consecutive meeting. Weaker-than-expected job growth further suggested that the Fed’s efforts to slow the economy were having an effect. “To me, the jobs report is an unquestionable positive,” said Ronald Temple, chief market strategist at Lazard. “I think it’s a really good signal to the Fed that they are slowing the economy and that they don’t need to raise rates again.” The 10-year Treasury yield is on course to end the week at around 4.5 percent, down roughly 0.3 percentage points for the week, its largest drop since the week the cryptocurrency exchange FTX collapsed last year. Still, the yield remains more than half a percentage point higher than it was at the start of August. This week’s dip in yields set off a broad rally across stock markets. The Russell 2000 index of smaller companies, which are more sensitive to the ebb and flow of the economy, rose nearly 3 percent on Friday. That index had fallen over 18 percent in recent months.