Chart of the Day: Voice calls are rapidly falling out of favour in Singapore

Mobile data is taking its place.

Widely popular voice messaging apps and similar free online services are taking a bite out of telcos' mobile voice revenue.

Barclays noted in a report that although voice services still make up bulk of the three telcos' topline, mobile voice revenue has been steeply declining since the second quarter of 2013.

Voice revenue made up 50% of operators' revenue in 2Q15, down from a high of 59% in 2Q13. In the same period, wireless data revenue grew from 26% to a staggering 40%.

"We believe that (still rapidly) declining voice revenue is the main reason for this lacklustre service revenue trend. At the industry level, voice revenue is still declining by a high singledigit rate y/y every passing quarter, and voice still remains a significant part of overall service revenue," Barclays noted.