Results were dragged down by lower natural gas output, which declined 11.4% from the prior-year period due to CNQ's decision to shut production volumes and to allocate capital for oil projects that will provide higher return. CNQ shares have also been held back by operational challenges, continued weakness in natural gas prices and a fresh round of cost inflation in the oil sands regions. On Mar 19, Zacks Investment Research downgraded independent oil and gas explorer Canadian Natural Resources Ltd. ( CNQ ) to a Zacks Rank #4 (Sell).