The volume of email that marketers sent in the third quarter of 2016 (3Q16) jumped 19.8% from the third quarter of 2015 (3Q15), according to recent research from Experian Marketing Services.

The report was based on 3Q16 Experian email data for companies in six verticals: business products and services, consumer products and services, media and entertainment, multi-channel retailers, publishers, and travel.

Marketers in the consumer products and services vertical and the publishers vertical sent more than one-third more emails, on average, in the third quarter of 2016 compared with the third quarter of 2015.

Marketers' emails had lower email campaign bounce rates and unsubscribe rates, on average, in 3Q16 than in 3Q15.

Email click rates declined 12.5%, on average, in 3Q16 compared with 3Q15.

Email click rates have steadily declined as the share of clicks generated by smartphones has steadily increased. The researchers found a significant negative correlation (-0.92) between the overall click rate and mobile click rate metrics.

About the research: The report was based on 3Q16 Experian email data for companies in six verticals: business products and services, consumer products and services, media and entertainment, multi-channel retailers, publishers, and travel.