The Bank of Japan returns to the spotlight this week after it shocked global financial markets in December with a tweak to its stimulus program.

While all but one of 43 economists in a survey forecast the central bank to leave policy unchanged on Wednesday, many say they can’t rule out more action.

That’s partly because the BOJ’s messaging has become less clear following its doubling of a cap on 10-year bond yields. Gov. Haruhiko Kuroda in the past has characterized such a move as a rate hike, but last month said it was aimed at improving the sustainability of its stimulus framework.