Investor Jim Rogers joined Bill Gross, who runs the world’s biggest bond fund, in warning that a rout that sent Treasuries to their biggest loss last month in almost a year probably isn’t over.

The list of bond bears is growing after Goldman Sachs Group  ($158.72 1.31%) and Wells Capital Management also voiced concern. While unemployment rose in January, Labor Department revisions showed job gains at the end of last year were higher than previously reported, increasing speculation the Federal Reserve will curtail its debt purchases this year.

The Standard & Poor’s 500 Index rallied this month to approach a record.