(Bloomberg) -- The US dollar extended its gains, sending the currency toward its longest rally in years as the strength of the economy fuels speculation the Federal Reserve will keep interest rates elevated. The Bloomberg Dollar Spot Index, which is heavily weighted against the euro and yen, edged up Thursday, extending a three-day advance that’s pushed it up nearly 1%. That’s put it on track for its eighth weekly gain, the longest since the index begins in January 2005. The ICE dollar index has seen a similar jump, leaving it poised for the longest advance in 9 years. Most Read from Bloomberg Businessweek©2023 Bloomberg L.P.