Why Blackmores, Service Stream, Sydney Airport, & Webjet shares are dropping lower

In afternoon trade the S&P/ASX 200 Index (ASX: XJO) is on course to record another strong gain. At the time of writing, the benchmark index is up 0.85% to 6,736.6 points.

Four shares that have not been able to follow the market higher today are listed below. Here’s why they are dropping lower:

The Blackmores share price is down over 4% to $77.31. Investors appear to have been selling the health supplements company’s shares amid speculation that A2 Milk Company Ltd (ASX: A2M) is about to downgrade its guidance for FY 2021. Given the similar channels they sell in, investors may be worried that Blackmores could be underperforming.

Service Stream Limited (ASX: SSM)

The Service Stream share price has crashed a further 15% lower to…