Growth in Bing search advertising revenue has slowed further, according to the latest Microsoft company reports. Year-on-year growth in Microsoft search ad revenue was 9% in Q2 2019, the lowest level in over two years. This is a continuous slowdown from 17% in the second quarter of 2018.

This contrasts with the 12.6% growth in search adspend forecast for 2019 across WARC's 12 key markets. However, search investment is growing slower than the wider internet ad market.

Microsoft puts this falling growth down to lower ad volume, unsuprising given Bing's loss of market share, the dominance of Google and Amazon's increasing importance. Growing application of visual and voice search is only likely to further complicate the sector for Bing. Indeed, Microsoft is placing greater emphasis on its rapidly growing cloud and digital subscriptions businesses.