PRAGUE—The Czech National Bank (CNB) raised its main rate by 75 basis points on Thursday, surprising markets with its biggest hike since 1997 and sending a signal it would not allow inflationary expectations to grow further amid a price spike. The Czech economy, like others around the world, is facing rising costs as it grapples with global supply snags, growing transport and energy prices, and strong demand coming after coronavirus pandemic restrictions eased earlier this year. The Czech Republic, though, also has the European Union’s lowest unemployment rate, and a tightening labour market is putting further upward pressure on wages and raising price expectations of both consumers and companies, worrying the central bank. “This forceful increase in interest rates aims to support the return of inflation towards the target over the monetary policy horizon as well as the anchoring of firms’ and households’ inflation expectations,” Governor Jiri Rusnok told reporters …