July 28 (Reuters) - Calfrac Well Services Ltd CFW.TO
* Co is optimistic that 2017 activity will improve year-over-year, but visibility remains uncertain at this time
* Calfrac announces second quarter results
* Q2 revenue c$150.6 million versus I/B/E/S view c$151.9 million
* Q2 loss per share c$0.36
* Q2 earnings per share view c$-0.38 -- Thomson Reuters I/B/E/S Source text for Eikon: ID:nCNWC8rh7a Further company coverage: CFW.TO
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