Bond sales worldwide are reviving from the slowest month of theyear as yields on corporate debt decline to the least since2010.

GlaxoSmithKline Plc's $5 billion offering, its firstdollar-denominated sale in more than four years, led issuance of atleast $55.1 billion this week following $45.8 billion in the periodended April 27, according to data compiled by Bloomberg.Stockholm-based Ericsson AB, the biggest maker of mobile phonenetworks, sold $1 billion of 10-year bonds to refinance existingdebt, its first issue in almost three years.

Borrowing costs are declining as investor demand rises amidoptimism that the global economy isn't slowing enough to dentcorporate creditworthiness. Some 71 percent of U.S. companies thathave reported first-quarter earnings beat analysts' estimates, datacompiled by Bloomberg show. Mutual fund inflows for fixed-incomefunds globally rose last week to the highest level since March,according to research firm EPFR Global.